UNIVERSITY  OF  CALIFORNIA 
AT  LOS  ANGELES 


THE  PSYCHIC  LIFE 


MICRO-ORGANISMS 


A  STUDY  IN  EXPERIMENTAL  PSYCHOLOGY 


ALFRED  BINET 


6 73 


REPRINT 


CHICAGO 

THE  OPEN  COURT  PUBLISHING  COMPANY 

(LONDON:  17  Johnson's  Court,  Fleet  St.,  E.  C.) 

1897 


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TRANSLATION  SANCTIONED  BY  THE  AUTHOR 


COPYRIGHT  BY 

THE  OPEN  COURT  PUBLISHING  Co. 
1888. 


I&F 
3.51  E 

PREFACE  TO  THE  AMERICAN  EDITION. 


I  HAVE  endeavored,  in  the  following  essay  upon  Micro-organ- 
isms, to  show  that  psychological  phenomena  begin  among  the  very 
lowest  classes  of  beings;  they  are  met  with  in  every  form  of  life 
from  the  simplest  cellule  to  the  most  complicated  organism.  It  is 
they  that  are  the  essential  phenomena  of  life,  inherent  in  all  pro- 
toplasm. 

We  admit,  accordingly,  the  existence  of  a  vitalism,  that  is  to 
say,  of  an  aggregate  of  properties  which  properly  pertain  to  living 
matter  and  which  are  never  found  in  inanimate  substances.  Among 
these  properties  of  life  we  classify  psychological  phenomena. 

Vitalism,  it  is  unnecessary  to  say,  has  nothing  in  common  with 
the  doctrine  upheld  by  the  School  of  Montpellier.  The  principle 
here  involved  has  nothing  to  do  with  properties  and  forces  that  are 
superadded  to  living  matter;  it  concerns  the  properties  that  are  in- 
herent in  it — the  properties  that  characterize  life. 

The  modern  opponents  of  vitalism  seek  to  confute  the  theory 
by  attempting  to  explain  all  phenomena  of  life  from  physico-chem- 
ical forces.  They  maintain  that  according  as  physiology  advances 
the  tendency  is  to  relegate  all  phenomena  nominally  physiological 
into  the  domain  of  physics  and  chemistry;  and  that  it  would  be 
only  a  question  of  time,  if  as  yet  they  had  not  succeeded  in  dem- 
onstrating that  every  vital  process  is  founded  upon  mechanical 
phenomena. 

In  a  recent  treatise  upon  "Vitalism  and  Mechanism,"*  M. 
Bunge,  professor  of  physiology  at  Basel,  has  shown  that  the  his- 
tory of  physiology  disproves  these*  hypotheses.  The  more  closely 


*  G.  Bunge,  Vitalismus  und  Mechanismus,  Ein  Vortrag,  18 


iv  PREFACE. 

the  phenomena  of  life  are  scrutinized,  the  more  carefully  they  are 
studied  in  their  various  aspects,  the  more  certain  does  the  conclu- 
sion become  that  the  processes  attributed  to  physico-chemical  forces 
in  reality  obey  much  more  complicated  laws.  To  illustrate,  it  was 
at  one  time  conceded  that  the  phenomena  of  resorption  and  nutri- 
tion were  explainable  by  diffusion  and  endosmosis;  Dutrochet. 
upon  his  discovery  of  endosmosis,  imagined  even  that  he  had  dis- 
covered the  principle  of  life.  At  the  present  time  we  know  that  the 
walls  of  the  intestines  do  not  in  any  wise  act  like  the  inanimate 
membrane  used  in  experiments  in  endosmosis.  They  are  covered 
with  epithelial  cells,  each  of  which  is  an  organism  endowed  with  a 
complex  of  properties.  The  protoplasm  of  these  cells  lays  hold  of 
food  by  an  act  of  prehension,  exactly  as  the  ciliate  Infusoria  and 
other  unicellular  organisms  do,  that  lead  an  independent  life.  In 
the  intestines  of  cold-blooded  animals  the  cells  emit  prolongations 
wnich  seize  the  minute  drops  of  fatty  matter  and,  carrying  them 
into  the  protoplasm  of  the  cell,  convey  them  thence  into  the  chyli- 
factive  ducts.  There  is  still  another  mode  of  absorption  of  fatty 
matters,  met  with  among  cold-blooded  as  well  as  warm-blooded 
animals:  the  lymphatic  cells  pass  out  from  the  adenoid  tissue  which 
contains  them,  so  that  upon  arriving  at  the  surface  of  the  intestines 
they  seize  the  particles  of  fatty  matter  there  present  and,  laden 
with  their  prey,  make  their  way  back  to  the  lymphatics. 

Accordingly,  the  faculty  of  seizing  food  and  of  exercising  a 
choice  among  foods  of  different  kinds — a  property  essentially  psy- 
chological— appertains  to  the  anatomical  elements  of  the  tissues, 
just  as  it  does  to  all  unicellular  beings,  in  the  manner  shown  in  our 
treatise.  It  is  plainly  impossible  to  explain  these  facts  by  the  in- 
troduction of  physico-chemical  forces.  They  are  the  essential  phe- 
nomena of  life  and  are  the  exclusive  appurtenance  of  living  pro- 
toplasm. 

If  the  existence  of  psychological  phenomena  in  lower  organ- 
isms is  denied,  it  will  be  necessary  to  assume  that  these  phenom- 
ena can  be  superadded  io  the  course  of  evolution,  in  proportion  as 


PREFACE.  v 

an  organism  grows  more  perfect  and  complex.  Nothing  could  be 
more  inconsistent  with  the  teachings  of  general  physiology,  which 
shows  us  that  all  vital  phenomena  are  previously  present  in  non- 
differentiated  cells. 

Furthermore,  it  is  interesting  to  note  to  what  conclusion  the 
admission  would  lead — as  Romanes  apparently  does  admit — that 
psychological  properties  are  wanting  in  lower-class  beings  and  that 
they  enter  at  different  stages  of  zoological  development.  Romanes 
has  minutely  particularized  on  a  large  chart  the  development  of  the 
intellectual  powers,  in  quite  an  arbitrary  manner.  According  to 
his  scheme,  only  protoplasmic  movements,  and  the  property  of 
excitability  are  present  in  lower-class  organisms.  Memory  begins 
first  with  the  echinoderms;  the  primary  instincts  with  the  larvae  of 
insects  and  the  Annelids;  the  secondary  instincts,  with  insects  and 
spiders;  reason,  finally,  commences  with  the  higher  Crustaceans. 

I  do  not  hesitate  to  say  that  all  this  laborious  classification  is 
artificial  in  the  extreme,  and  perfectly  anomalous. 

All  writers  that  have  devoted  themselves,  with  any  pretension 
to  special  investigation,  to  the  study  of  unicellular  organisms,  have 
attributed  to  these  beings  most  of  the  psychological  properties 
which  M.  Romanes  reserves  for  this  or  that  higher-class  animal. 
This  is  the  opinion  of  Gruber,  of  Verworn,  of  Moebius,  of  Balbiani, 
and  of  many  other  naturalists.  Mcebius  recognizes  that  psycho- 
logical life  begins  with  living  protoplasm,  and  he  considers  it  to  be 
the  highest  aim  of  zoology  to  demonstrate  the  psychical  unity  of  all 
animals. 

We  could,  if  it  were  necessary,  take  every  single  one  of  the 
psychical  faculties  which  M.  Romanes  reserves  for  animals  more 
or  less  advanced  on  the  zoological  scale,  and  show  that  the  greater 
part  of  these  faculties  belonged  equally  to  Micro-organisms.  But 
we  must  not  unnecessarily  extend  the  discussions  of  this  introduc- 
tion. We  shall  accordingly  limit  ourselves  to  few  illustrations. 

M.  Romanes,  in  his  zoological  scale,  assigns  the  first  manifes- 
tations of  surprise  and  fear  to  the  larvae  of  insects  and  to  the  An- 


vi  PREFACE. 

nelids.  We  may  reply  upon  this  point,  that  there  is  not  a  single 
ciliate  Infusory  that  cannot  be  frightened,  and  that  does  not  mani- 
fest its  fear  by  a  rapid  flight  through  the  liquid  of  the  preparation. 

If  a  drop  of  acetic  acid  be  introduced  beneath  the  glass-slide,  in 
a  preparation  containing  quantities  of  Infusoria,  the  latter  will  at 
once  be  seen  to  flee  from  all  directions  like  a  flock  of  frightened 
sheep. 

Memory,  according  to  M.  Romanes,  first  begins  with  the 
Echinoderms.  Now,  Moebius,  upon  the  occasion  of  a  treatise  upon 
the  Folliculina  ampulla*  a  ciliated  Infusory  presenting  complicated 
and  interesting  movements,  properly  remarks  that  every  time  an 
animal  repeats  the  same  action  under  influence  of  the  same  excita- 
tions, that  fact  proves  that  the  animal  is  possessed  of  memory.  In 
fact,  memory  is  one  of  the  most  elementary  of  psychological  facts. 

Lastly,  the  primary  instincts,  according  to  M.  Romanes,  begin 
first  with  the  larvae  of  insects  and  with  Annelids.  We  give,  in  con- 
tradiction of  this  statement,  the  recent  observations  of  Verworn,  f 
which  reveal  the  existence  of  curious  instincts  among  the  Rhizopods. 
The  Dijflugia  itrceoiata,  which  inhabits  a  shell  formed  of  particles 
of  sand,  emits  long  pseudopodia  which  search  at  the  bottom  of  the 
water  for  the  materials  necessary  to  construct  a  new  case  for  the 
filial  organism  to  which  it  gives  birth  by  division.  The 
pseudopod,  after  having  touched  a  particle  of  sand,  contracts,  and 
the  grain  of  sand,  adhering  to  the  pseudopod,  is  seen  to  pass  into 
the  body  of  the  animal..  Verworn,  instead  of  grains  of  sand, 
placed  small  fragments  of  colored  glass  about  the  animal;  some 
time  afterwards,  he  noticed  a  heap  of  these  fragments  on  the  bot- 
tom of  the  shell.  He  then  saw  a  bunch  of  protoplasm  issue  from 
the  shell,  representing  the  new  Dijflugia  produced  by  division. 
Thereupon,  the  materials  collected  by  the  mother-organism — the 
fragments  of  colored  glass — came  forth  from  the  shell  and  envel- 
oped the  body  of  the  new  individual  in  a  sheath  similar  to  that  en- 


•  Moebius,  Das  Flaickenthirrcheit,  Folliculina  ampulla,  1887. 

t  Verworn,  Zeitickri/t/Ur  WisttnsckaftlUht  Zootofit,  Bd.  46.  H.  4.     1888. 


PREFACE.  vn 

casing  the  mother.  These  fragments  of  glass,  loosely  interjoined 
at  first,  were  now  cemented  together  by  a  substance  secreted  by 
the  body  of  the  animal. 

Two  facts  are  to  be  remarked  in  this  observation:  first,  the  act 
whereby  the  DiJJlugia  collects  the  materials  for  providing  the  young 
individual  with  a  case,  is  an  act  of  preadaptation  to  an  end  not 
present,  but  remote;  this  act,  therefore,  has  all  the  marks  of  an 
instinct.  Further,  the  instinct  of  the  Difflugia  exhibits  great  pre- 
cision; for  the  Difflugia  not  only  knows  how  to  distinguish,  at  the 
bottom  of  the  water,  the  materials  available  for  its  purpose,  but  it 
takes  only  the  quantity  of  material  necessary  to  enable  the  young 
individual  to  acquire  a  well-built  case;  there  is  never  an  excess. 

It  is  interesting  to  note  that  the  Difflugia  does  not  act  differ- 
ently from  animals  possessing  more  highly  complicated  organiza- 
tions and  endowed  with  differentiated  nervous  systems,  as  for  in- 
stance, the  larva?  of  Phryganids  which  form  their  sheaths  from 
shells,  grains  of  sand,  or  minute  slivers. 

We  shall  not  regard  it  as  strange,  perhaps,  to  find  so  complete 
a  psychology  in  the  history  of  lower  organisms,  when  we  call  to 
mind  that,  agreeably  to  the  ideas  of  evolution  now  accepted,  a  higher 
animal  is  nothing  more  than  a  colony  of  protozoans.  Every  one  of 
the  cells  composing  such  an  animal,  has  retained  its  primitive  proper- 
ties, giving  them  a  higher  degree  of  perfection  by  division  of  labor 
and  by  selection.  The  epithelial  cells  that  secrete  the  nails  and  the 
hair  are  organisms  perfected  with  reference  to  the  secretion  of 
protective  parts.  Similarly,  the  cells  of  the  brain  are  organisms 
that  have  been  perfected  with  reference  to  psychical  attributes. 

PARIS,  November  20,  1888. 

ALFRED  BINET. 


TABLE  OF  CONTENTS. 


INTRODUCTORY. 

Pages 

A  branch  of  Comparative  Psychology  little  known. — Defini- 
tion of  Micro-organisms.  —  Their  classification. —  Main 
groups  of  animal  Micro-organisms. — Complexity  of  their 
life  of  relation. — The  Micro-organism  not  simply  an  irrita- 
table  cellule 1-4 

L 
THE  MOTORY  ORGANS  AND  THE  ORGANS  OF  SENSE. 

MOTORY    ORGANS. 

Motility. — The  pseudopod.— Opinion  of  M.  Rouget  relative 
to  the  formation  of  pseudopods. — The  vi  bra  tile  cilia. — 
Their  morphological  significance. — Observations  of  Engel- 
mann. — The  movements  of  the  vibratile  cilia  are  subject 
to  the  will  of  the  animal. — Observations  of  M.  Balbiani 
upon  the  Didinium  nasutum. — Experiments  of  Rossbach. 
— The  flagellum. — Diversity  of  its  movements. — Observa- 
tion of  Butschli  upon  the  flagellum  of  the  Glenodinium 
cine  turn. — Metabolic  infusoria. — The  granulous  bands  and 
bright  filaments. — The  contractile  vesicle. — The  move- 
ments of  Bacteria  and  Gregarinae 4-20 

THE   NERVOUS   SYSTEM. 

Absence  of  a  central  nervous  system  in  single-celled  organ- 
isms.— Hypothesis  of  a  diffused  nervous  system. — Obser- 
vation of  Gruber  upon  the  Stentor  in  process  of  division .  20-22 

THE    ORGANS    OP    SENSE. 

Organs  of  touch. — Organs  of  sight. — Ocular  spot  in  Flag- 
ellates.— Ocular  spot  of  vegetable  zoospores. — Experi- 
ments of  Klebs  upon  the  structure  of  these  spots. — The 


CONTENTS.  ix 

Pages 
hematochrome  is  not  without  analogy  to  the  chlorophyl 

pigment. — Opinion  of  naturalists  upon  the  physiological 
function  of  the  so-called  ocular  spots. — Observation  of 
M.  Pouchet  upon  the  eye  of  the  Glenodinium  polyphemus. 
—  This  eye  is  composed  of  a  pigmentary  mass  and  of  a 
refringent  body. — Observations  of  M.  Kunstler  upon  the 
eye  of  Phacus. — Observation  of  Claparede  and  Lach- 
mann. — Observation  of  Lieberkiihn. — Sensitiveness  of  the 
Euglena  to  light. — Experiments  of  Engelmann. — The  vesi- 
cles of  Muller  in  the  Loxodes  rostrum 22-31 

ii. 
NUTRITION. 

Psychical  phenomena  connected  with  respiration. — Search 
for  oxygen  by  the  bacteria  of  putrefied  matter. — Observa- 
tion of  Engelmann 3i~34 


THE    PSYCHOLOGY    OF    NUTRITION. 

Psychical  phenomena  connected  with  nutrition. — Vegetable, 
or  holophytic,  nutrition. — The  chromatophores.— Structure 
ot  the  chromatophores. — Coincidence  between  the  presence 
of  an  eye  and  that  of  chlorophyl  pigment. — Comparison 
between  the  Euglena  and  the  Peranema. — Nutrition  by 
endosmosis,  or  saprophytic. — Animal  nutrition,  choice  of 
nutriment. — Prehension  of  foods  by  the  Amoeba,  the  Actin- 
ophrys,  the  Monas,  the  Acineta. — Opinion  of  M.  Mau- 
pas  upon  choice  by  preference. — Capture  of  food. — The 
vorticel  Ciliates.  —The  Hunter  Ciliates.  — The  Amphileptus. 
— The  Didinium  nasutum. — Movements  of  defense  and 
flight 34-55 

IV. 
COLONIES    OF    UNICELLULAR    ORGANISMS. 

Colonies  of  unicellular  organisms. — Colonies  of  single-celled 
organisms  have  their  origin  in  the  segmentations  of  a 
mother-cellule.— Temporary  colonies  which  are  formed 
beneath  the  cuticle. —The  Gonium. — The  Eudoryna.-— The 


x  CONTENTS. 

Pates 

Volvox. — Difference  between  a  pluricellular  organism  and 

a  colony  of  unicellular  organisms. — Voluntary  combina- 
tions.— The  Bodo  caudatus 55~6i 

v. 
THE    PSYCHOLOGY   OF    PROTO-ORGANISMS. 

Remarks  upon  the  psychology  of  Micro-organisms. — Their 
various  actions  are  direct  responses  to  stimuli  from  the  out- 
ward world. — Perception  of  external  bodies. — Choice. — 
Calculation  of  the  positions  occupied  by  external  bodies. 
— Movements  of  Micro-organisms 61-65 


FECUNDATION. 

Fecundation  among  Infusoria. — Historical. — Psychological 
preliminaries  of  fecundation — Observations  of  M.  Bal- 
biani  upon  the  Paramaecia,  the  Spirostomes,  and  the  Sten- 
tors. — Copulation. — Fecundation  among  the  Vorticels. — 
Observation  of  Engelmann.  — Material  phenomena  in  fec- 
undation.— The  role  of  the  nucleus,  and  the  role  of  the 
nucleolus. — Description  of  the  phenomena  as  seen  in  the 
Chilodon  cucullulus  (see  appendix),  the  Paramacium  bursa- 
ria  and  in  the  Paramacium  aurelia. — Observation  of  M. 
Balbiani  upon  Paramaecia,  of  which  the  nucleus  is  overran 
with  parasites 65~75 

VII. 
FECUNDATION    IN    HIGHER    ANIMALS    AND   PLANTS. 

Fecundation  in  higher  animals  and  plants. — The  spermato- 
zoid  and  the  ovule  can  be  compared  to  Micro-organisms. — 
The  elements  can  live  for  a  certain  time  independent  of 
the  animals  from  which  they  come. — Their  motor  organs. 
— The  movements  of  the  spermatozoid  towards  the  ovule. 
— Length  of  road  to  be  traveled. — Obstacles  to  be  over- 
come.— Windings  and  intricacies  of  the  path. — The  sper- 
matozoid of  the  silk-worm. — Arrival  of  the  spermatozoid  in 
contact  with  the  ovule. — Observation  of  Fol  upon  the 
fecundation  of  the  star-fish. — The  cone  of  attraction. — 


CONTENTS.  xi 

Pages 
Sexual  selection  operating  as  between  different  spermato- 

zoids. — Movements  of  the  female  element. — Vegetable 
fecundation. — Progressive  differentiation  of  the  two  sex- 
ual elements. — Sexual  reproduction  of  the  Ectocarpus  sili- 
culosus,  after  Berthold. — Investigations  of  Pfeffer  upon 
the  spermatozoids  of  cryptogams. — Action  of  certain 
chemical  excitants  upon  these  elements. — Specific  charac- 
ter of  the  excitant. — The  threshold  of  excitation. — Appli- 
tion  of  Weber's  law 75~9i 


THE    PHYSIOLOGICAL    FUNCTION    OF    THE 
NUCLEUS. 

Functions  attributed  to  the  protoplasm  and  to  the  envelop- 
ing membrane. — The  nucleus,  its  histological  importance 
proved  by  the  phenomena  of  caryokinesis. — Balbiani  and 
Gruber  have,  at  times,  observed  Infusoria  and  Actinophrys 
deprived  of  nuclear  substance. — Nussbaum's  and  Gruber's 
experiments  of  vivisection  upon  the  Stentor  cceruleus. — 
Fragments  provided  with  nucleus  reconstruct  themselves. 
— Experiments  of  Balbiani — Facts  observed  by  Gruber, 
in  general,  confirmed. — Error  of  Gruber  respecting  frag- 
ments without  nucleus. — These  fragments  do  not  con- 
tinue to  live,  their  plasma  undergoes  disorganization. 
—  Experiments  of  division.  —  Experiments  made  upon 
Infusoria  while  in  conjugation. — The  presence  of  the 
old  nucleus  in  a  severed  fragment  only  brings  about 
an  incomplete  regeneration. — The  nucleus  presides  over 
all  physiological  functions,  the  totality  of  which  con- 
stitutes life. — The  regenerative  and  reproductive  property 
of  the  plasma  is  lost  before  the  psychical  functions  are. — 
Agreement  of  all  these  facts  with  the  phenomena  ob- 
served as  taking  place  during  the  spontaneous  division  of 
Micro-organisms 92-105 

IX. 

CONCLUSION. 

Statement  of  M.  Richet's  position  respecting  cellular  psy- 
chology           105 


xii  CONTENTS. 

Pages 
Romanes's   conception  of  the  psychic  activity  of  Proto- 

organisms 105 

Irritability  and  cellular  psychology 107-110 

Correspondence  between  Ch.  Richet  and  Alfred  Binet,  ap- 
pearing in  the  Revue  Phitosofhique  of  February,  1888,  re- 
printed from  THE  OPEN  COURT  of  December  27,  1888.110-115 

APPENDIX. 

Additional  cuts  illustrative  of : 

The  Conjugation  of  the  Paramacium  aurelia 116 

The  Conjugation  of  the  Slentor  ccerulfus 116 

The  Copulation  of  the  Stylonithia  mytilus 1 16 

The  Conjugation  of  the  Carchesium  polypinum 117 

The  Conjugation  of  the  Chilodon  cucul lulus  (with  explana- 
tions)    118 

Addenda.    Notes  and  References  omitted  in  the  text. .  121 


THE  PSYCHIC  LIFE  OF   MICRO-ORGANISMS. 


THE  study  of  microscopic  organisms  has  hitherto 
been  somewhat  neglected  by  students  of  comparative 
psychology.  Naturalists  who  have  devoted  their  at- 
tention to  the  study  of  these  beings,  have  collected  a 
great  number  of  interesting  facts  concerning  their 
psychic  life;  but  these  facts  have  not  yet  been  critically 
examined  and  collated;  they  are  scattered  in  reports 
and  publications  of  all  kinds,  where  the  psychologist 
never  dreams  of  looking  for  them.  We  shall  endeavor 
to  make  him  acquainted  with  a  part  of  this  wealth. 

Under  the  name  Micro-organism  are  included  all- 
those  beings  which  by  reason  of  their  extreme  smallness 
and  simplicity  of  structure  represent  the  lowest  stages 
of  animal  or  vegetable  life;  they  constitute  the  very  sim- 
plest forms  of  living  matter,  and  .consist  of  a  single  cell. 
Some  inhabit  fresh  and  salt  waters,  serving  as  food 
for  a  great  many  other  organisms,  or  contributing  by 
means  of  their  calcareous  or  silicious  skeletons  to  the 
formation  of  continents.  Others  live  as  parasites  in 
the  organs  of  animals  and  plants,  and  induce  more  or 
less  serious  disorders  in  the  constitutions  of  the  organ- 
isms they  have  penetrated.  Others,  again,  acting  like 
ferments  produce  important  chemical  modifications  in 
organic  matter  in  the  course  of  decomposition. 

A  great  number  of  classifications  for  the  methodical 
distribution  of  these  beings  has  been  proposed;  but 
not  one  of  them  is  altogether  satisfactory;  and  that 


2  THE  PSYCHIC  LIFE 

stands  to  reason.  If  a  natural  classification  is  always 
a  complex  piece  of  work  in  the  case  of  the  higher  ani- 
mals which  differ  from  each  other  in  important  features 
and  between  which  a  comparison  can  be  instituted, 
the  difficulty  attending  the  classification  of  simple  or- 
ganisms which  present  only  the  slightest  differentia- 
tions is  still  more  difficult. 

The  principal  division  made  is  that  which  divides 
them  into  animal  Micro-organisms  or  Protozoans  and 
vegetable  Micro-organisms  or  Microphytes. 

The  line  of  demarcation  between  these  two  king- 
doms is  far  from  being  well  defined;  there  are  a  great 
number  of  micro-organisms  incerta  sedis,  which  bota- 
nists usually  place  in  the  vegetable  kingdom,  but  which 
zoologists  prefer  to  classify  as  belonging  to  the  ani- 
mal kingdom.* 

We  give  below  a  list  of  the  most  important  groups 
of  animal  micro-organisms. 

ANIMAL  MICRO-ORGANISMS. 

INFUSORIA.  MASTIGOPHORES.       SARCODINES.  SPOROZOA. 

Ciliates  Flagellates.  Rhizopods.  Gregarinida. 

Suctoria  (Suckers)  Choanoflagellates.    Heliozoa.  Coccidia. 

Dinofiagellates.         Radiolarians.  Sarcosporidia. 

Cystoflagellates My  xosporidia. 

Microsporidia. 

We  propose,  now,  to  study  the  psychic  life  of  these 
lower  organisms,  or,  to  speak  in  more  general  terms, 
their  life  of  relation.  It  is  well  known  that  the  expres- 
sion, the  life  of  relation,  comprehends  essentially  two  dis- 
tinct ideas:  first,  the  action  of  the  external  world  felt 
by  the  organism:  or  sensibility;  secondly,  the  reac- 
tion of  the  organism  on  the  external  world:  or  move- 

*The  best  mark  to  distinguish  the  two  kingdoms  is  the  chemical  nature  of 
the  enveloping  membrane:  in  the  case  of  vegetable  organisms,  the  enveloping 
membrane  is  made  up  of  a  ternary  substance,  cellulose;  while  in  animal  organ- 
isms it  is  albuminoid  in  character. 


OF  MICR  O-  OR  GANISMS.  3 

ment.  It  is  customary  to  apply  to  the  union  of  these 
two  properties  the  name  irritability,  which  expresses 
the  reaction  of  the  micro-organism  upon  exterior 
forces.  It  is  therefore  held,  and  with  reason,  that 
every  living  cell  is  irritable,  that  is  to  say  that  it  pos- 
sesses the  property  of  responding  by  movements  to 
the  excitations  which  it  suffers. 

In  admitting  then  that  irritability  is  the  founda- 
tion of  the  life  of  relation,  and  consequently  also  the 
foundation  of  psychology,  we  must  nevertheless  guard 
against  comparing  the  autonomous  cell  of  micro- 
organisms to  a  simple  irritable  cell.  Although  the 
body  of  these  small  beings  may  be  equivalent  to  a 
simple  cell,  it  would  be  an  error  to  believe  that  their 
life  of  relation  consists  in  a  motory  reaction  consequent 
upon  exterior  irritation.  At  the  close  of  our  investiga- 
tions into  the  psychology  of  Proto-organisms  we  shall 
see  that,  in  these  inferior  beings  which  represent  the 
simplest  forms  of  life,  we  find  manifestations  of  an  in- 
telligence which  greatly  transcends  the  phenomena  of 
cellular  irritability.  Thus,  even  on  the  very  lowest 
rounds  of  the  ladder  of  life,  psychic  manifestations  are 
very  much  more  complex  than  is  usually  believed,  and 
the  conception  of  cellular  psychology  which  some  very 
recent  authors  have  formed,  seems  to  me  a  very  crude 
analysis  of  the  most  delicate  of  phenomena. 

In  the  great  majority  of  pluricellular  animals,  the 
life  of  relation  is  exhibited  in  a  nervous  system  and 
in  a  muscular  system.  In  Micro-organisms  the  same 
cannot  be  said  to  be  the  case:  the  greater  part  possess 
neither  a  central  nervous  system  nor  organs  of  sense; 
some  even  lack  organs  of  locomotion.  The  functions 
of  the  life  of  relation  are  performed  by  the  entire 
mass  of  the  body:  many  of  the  Protista,  for  example, 


4  THE  PSYCHIC  LIFE 

have  not  a  trace  of  an  anatomically  differentiated 
visual  organ;  it  is  the  entire  protoplasm  of  the  ele- 
mentary organism  that  is  excitable  by  light,  as  it  is 
also  by  heat  or  by  electricity.  In  other  Micro-organ- 
isms somewhat  higher  in  the  scale,  a  beginning  of 
differentiation  may  be  seen  to  make  its  appearance, 
giving  birth  either  to  some  organ  of  sense  or  to  some 
organ  of  locomotion. 

We  shall  give  a  general  description  of  these  organs. 
The  study  of  this  first  move  in  the  work  of  differentia- 
tion is  of  great  interest  to  comparative  anatomy  and 
physiology;  no  less  interesting  is  it  to  psychology. 
Besides  dwelling  on  these  preliminaries  of  our  work, 
we  shall  have  occasion  to  note  new  and  interesting 
facts. 

I. 

THE  MOTORY  ORGANS  AND  THE  ORGANS  OF  SENSE. 

Motility.  From  the  schedule  of  the  groups  of  ani- 
mal micro-organisms  which  we  have  given,  it  will 
be  seen  that  they  are  subdivided  into  four  classes, 
the  Infusoria,  the  Mastigophores,  the  Sarcodines  and 
the  Sporozoa.  The  distinction  between  these  classes 
depends  on  the  existence  and  the  nature  of  the  motor 
organs. 

The  Infusoria  comprise  the  protozoa  that  move  by 
the  aid  of  vibratile  cilia  distributed  in  greater  or  less 
number  over  their  body. 

The  second  class,  the  Mastigophores,  comprises 
those  animals  which  move  by  the  aid  of  flagella,  that 
is  to  say  by  the  help  of  long  filaments. 

The  third  class,  the  Sarcodines,  comprises  those 
animals  which  move  by  the  aid  of  pseudopodia;  which 
are  projections  of  the  substance  of  their  bodies. 

The  fourth  class,  the  Sporozoa,  is  characterized  by 


OF  MICR  O-  OR  GANISMS.  5 

the  mode  of  multiplication:  they  are  reproduced  by 
spores.  In  the  animals  of  this  group,  the  special 
motor  organs  are  wanting;  these  creatures  therefore 
generally  move  very  little,  or  they  present  only  move- 
ments of  which  the  principles  are  unknown. 

We  shall  successively  describe  the  pseudopodia, 
the  vibratile  cilia  and  the  flagellum. 

The  Pseudopod.  The  formation  of  pseudopodia 
takes  place  chiefly  in  naked  cells — in  cells  lacking  an 
enveloping  membrane,  in  the  Sarcodines  in  general. 
They  can  easily  be  studied  in  the  Amoeba  princeps,  a 
microscopic  animal  which  is  found  in  abundance  in 
fresh  water  containing  organic  matter  in  a  state  of 
putrefaction.  It  has  the  aspect  of  a  small  gelatinous 
mass,  irregular,  formed  of  a  colorless  substance,  the 
protoplasm.  The  chemical  nature  of  protoplasm  is 
still  very  imperfectly  understood;  it  is  only  known 
that  it  is  the  result  of  a  mixture  of  albuminoid  mat- 
ters, with  an  addition  of  water  and  mineral  elements. 
In  the  protoplasm  of  the  amoeba  exists  a  small  rounded 
and  refracting  mass,  containing  one  or  two  bright  cor- 
puscles in  its  interior;  this  small  mass  is  called  the 
nucleus,  and  the  corpuscles  the  nucleoli. 

The  form  of  the  body  of  the  amceba  is  rendered 
very  irregular  by  the  fact  that  certain  parts  of  the 
mass  lengthen,  and  form  short  and  rounded  protuber- 
ances which  are  designated  by  the  name  of  pseudo- 
podia. It  is  by  means  of  these  pseudopodia  that  the 
animal  moves;  it  emits  them  in  the  direction  in  which 
it  is  going,  then  it  retracts  them,  while  other  parts  of 
the  mass  are  in  their  turn  elongated.  The  whole  body 
moves  by  creeping.  The  amceba  in  moving  has  the 
aspect  of  a  drop  of  oil  moving  along.  To  explain  the 
mechanism  of  this  movement,  it  must  be  supposed 


6  THE  PSYCHIC  LIFE 

that  the  extended  pseudopod  seizes  some  point  of  sup- 
port with  its  free  end,  then,  in  contracting,  draws  the 
entire  mass  of  the  body  up  to  this.  But  it  is  difficult 
to  understand  what  the  cause  of  the  elongation  of  the 
pseudopodia  is.  It  has  been  supposed  that  the  pro- 
toplasm is  endowed  with  great  elasticity  and  that  the 
elongation  is  the  return  of  this  substance  to  its  primi- 
tive form.  That  is  not  the  explanation  given  by  M. 
Rouget.  The  learned  professor  of  the  Museum  has 
been  kind  enough  to  write  out  the  following  note  for 
us,  in  which  he  recapitulates  his  opinion: 

"Every  time  that  a  protoplasmic  organism  dies,  or 
is  subjected  either  to  a  strong  electric  excitation,  or 
to  a  relatively  high  temperature  (4-  45°  to  +  50°), the 
pseudopodia  are  retracted  and  re-enter  into  the  mass, 
which  assumes  a  globular  form;  the  same  is  the  case 
in  the  protoplasm  of  vegetable  cells,  the  inter-cellular 
reticulum  of  which  breaks  in  receding,  or  else  the  mass 
of  protoplasm  divides  into  spherical  bodies.  These 
states  of  retraction  are  the  analogues  of  muscular 
rigidity,  and  like  it  represent  the  condition  of  maximum 
contraction  in  the  protoplasm — nevertheless  the  style 
of  the  Vorticels  (Carchesiuin)  which  is  a  protoplas- 
mic formation,  under  the  same  conditions,  remains  in 
a  state  of  permanent  retraction.  It  follows  from  this 
that  the  emission  of  the  pseudopodia,  their  elongation, 
cannot  in  any  case  be  considered  as  a  direct  act  of  the 
contractility  of  the  protoplasm. 

"The  production  of  the  pseudopodia,  one  of  the 
most  difficult  problems,  cannot,  in  my  opinion,  be  ex- 
plained, except  in  the  following  manner:  All  proto- 
plasmic masses,  and  especially  the  amoeba,  consist  of 
two  parts,  an  enveloping  membrane  or  ectosarc,  vis- 


OF  MICR  O-  OR  GANISMS.  7 

cous  and  elastic,  and  the  central  liquid  contents  hold- 
ing granules  in  suspension. 

"  From  the  time  of  the  apparition  of  a  pseudopod,  a 
current  of  liquid  is  visible  which  penetrates  into  the 
pseudopod  and  which  seems  to  contribute  to  its  elon- 
gation. It  is  very  evident  that  the  liquid  is  passive, 
that  it  penetrates  into  the  pseudopod  only  because, 
pressed  upon  from  all  sides,  it  finds  less  resistance 
there.  I  think  that  the  (in  appearance)  homogeneous 
hyaline  substance  of  the  pseudopod  is  also  a  species 
of  hernia  of  the  estosarc,  resulting  from  a  diminution 
of  the  elastic  resistance  at  the  point  where  it  appears, 
with  an  increase  of  elasticity  or  of  contractility  (to  me 
two  modalities  of  the  same  property)  in  those  parts  of 
the  ectosarc  where  pseudopodia  are  not  produced. 
When  the  contractility  or  the  elastic  tension  of  these 
parts  diminishes,  and  returns  to  its  original  state 
the  pseudopod  re-enters  into  the  mass.  Add  to  this 
that,  in  an  amoeba  of  large  dimensions,  Amoeba  terri- 
cola,  it  has  seemed  to  me  that  the  most  external  mem- 
brane of  the  ectosarc  showed  striae  of  a  granular  ap- 
pearance which  may  be  identical  with  the  stria?  or  con- 
tractile fibrils  of  the  ectosarc  of  the  ciliated  infusoria, 
St  enter, Spirostomes,  Bursaria,  etc."  (May  20,  1887.) 

The  pseudopod  does  not  represent  a  permanent, 
differentiated  organ  of  locomotion;  it  is  produced  by  a 
simple  prolongation  of  the  mass  of  the  body,  which 
can  take  place  at  any  point  whatever,  and  when  the 
act  of  locomotion  has  been  accomplished,  this  pro- 
longation re-enters  into  the  common  mass  without 
leaving  any  traces  of  its  emission.  In  other  animal 
species,  for  example  the  Petalobus  of  Lachmann, 
initial  traces  of  differentiation  of  the  pseudopodia 
have  been  observed;  they  always  form  at  the  same 


8  THE  PSYCHIC  LIFE 

point  of  the  body,  on  a  level  with  the  anterior  part; 
but,  in  spite  of  this  constant  localization,  the  motor 
organ  has  only  a  transitory  existence;  it  is  produced 
at  the  moment  it  is  needed,  and  disappears  into  the 
mass  of  the  body,  when  the  movement  has  been  exe- 
cuted. In  the  Actinophrys  there  is  a  still  greater  pro- 
gress: the  numerous  pseudopodia  emitted  by  this  ani- 
mal, and  which  have  the  form  of  filaments,  are  perma- 
nent organs  with  definite  functions. 

The  Vibratile  Cilia.  The  vibratile  cilia  are  short, 
extremely  thin,  homogeneous  filaments  which  are  agi- 
tated by  a  vibratory  movement.  These  are  distinctly 
differentiated  organs  of  locomotion.  They  have, 
moreover,  several  functions:  firstly,  they  enable  the 
animal  to  move  about  in  the  liquid;  secondly,  they 
serve  it  as  an  organ  of  prehension;  thirdly,  they  per- 
mit a  renewal  of  the  water  which  furnishes  the  neces- 
sary air  for  respiration  to  the  animal;  perhaps  they 
also  serve  as  organs  of  touch. 

The  vibratile  cilia  lend  to  the  Infusoria  their  peculiar 
character  and  enable  them  to  be  distinguished  from 
all  the  other  Protozoa.  Cilia  are  also  found  in 
vegetable  species  when  young,  and  in  the  larvae  of 
Coelenterates,  of  mollusks  and  of  .worms.  But 
among  the  Protozoa,  it  is  the  Infusoria  alone  that  are 
ciliated.  The  cilia  are  distributed  in  various  manners, 
differing  according  to  the  species.  In  the  holotricha, 
they  are  distributed  regularly  over  the  whole  surface 
of  the  body,  and  almost  all  have  the  same  length;  in 
the  Heterotricha,  they  also  cover  the  whole  surface  of 
the  body,  but  they  are  unequal  in  length.  To  this 
group  belong  the  Stentors  which  have  long  cilia  in- 
serted around  a  circular  surface,  extending  almost  to 
the  mouth.  This  surface  is  a  rotatory  organ,  analo- 


OF  MICR  O-  OR G AN! SMS.  9 

gous  to  that  of  the  rotifers;  it  produces  eddies  in  the 
water  and  thus  causes  the  flow  of  foreign  bodies  to  the 
mouth:  these  animals  have  the  rest  of  their  bodies 
covered  with  fine  cilia.  In  the  Hypotricha  the  cilia 
are  located  on  the  ventral  surface  of  the  body  and  aid 
in  locomotion.  In  the  Peritricha,  they  form  a  cir- 
cular or  spiral  row  on  the  anterior  part  of  the  body, 
and  lead  to  the  mouth.  This  is  observed  in  the  Vor- 
ticels,  sessile  species  which  have  no  other  cilia  than 
those  which  are  used  for  the  prehension  of  food;  the 
rest  of  the  body  is  bare. 

Much  has  been  said  about  the  morphological  signif- 
icance of  vibratile  cilia;  several  micrographists  have 
held  that  the  cilia  are  attached  to  the  enveloping  mem- 
brane only,  and  have  no  connection  whatever  with  the 
protoplasm.  That  was  notably  the  opinion  of  Robin; 
it  is  entirely  wrong.  The  cilia  are  never  simple  pro- 
longations of  the  cuticle;  they  have  their  root  in  the 
protoplasmic  substance;  they  pass  through  orifices  in 
the  cuticle,  which  consequently  is  pierced  by  a  multi- 
tude of  small  holes.  Engelmann,  in  recent  observa- 
tions, has  been  able  to  trace  the  extremity  of  the  vibra- 
tile cilia  into  the  interior  of  the  protoplasm;  he  made 
this  observation  on  the  marginal  cilia  of  the  Stylo- 
nichia;  from  each  of  these  threads  he  has  seen  sep- 
arate a  pale  fibre,  which  moves  along  almost  directly 
beneath  the  cuticle  in  a  direction  perpendicular  to  the 
lateral  edge  of  the  body;  towards  the  median  line  of 
the  ventral  face  the  fibres  are  often  laid  bare,  because 
the  body  of  this  Infusory  voids  its  protoplasmic  sub- 
stance; there  the  fibres  have  the  aspect  of  tightened 
threads.  Engelmann  sees  in  this  observation  a  con- 
firmation of  the  opinion  that  the  bodies  of  infusoria 
are  formed  of  one  single  cell,  because,  according  to 


io  THE  PSYCHIC  LIFE 

other  observers,  there  exist  also  in  vibratile  cellules 
filiform  striae  which  seems  to  be  a  continuation  of  the 
cilia,  and  which  traverse  the  protoplasm  of  the  cell 
throughout  its  whole  length. 

We  might  add  to  this  direct  observation  several 
other  facts  showing  that  the  vibratile  cilia  are  indeed 
prolongations  of  the  plasm.  Under  the  action  of 
re-agents  the  cilia  act  like  the  cellular  protoplasm; 
they  are  coagulated  by  the  acids  and  dissolved  by 
weak  alkalies,  while  the  cuticle  offers  a  greater  resis- 
tance to  these  same  agents. 

These  vibratile  appendices  are  not  without  analogy 
with  the  pseudopodia  of  naked  cells;  Dujardin,  a 
French  naturalist,  demonstrated  this  in  1835,  although 
efforts  have  since  been  made  to  bestow  the  honor  of 
this  discovery  upon  the  Germans.  Dujardin  has 
proved  that  the  amoeboid  movement  and  the  ciliary 
movement  are  only  two  manifestations  of  the  con- 
tractile power  of  protoplasm.  In  fact,  if  instead 
of  examining  a  pseudopod  with  lobed  outline  like  that 
of  the  amo3ba,  we  observe  the  slender  and  filamentous 
pseudopodia  of  the  Foramenifera,  we  see  that  the  ex- 
tremity of  the  filament  is  agitated  by  the  same  vibra- 
tory movement  as  the  vibratile  cilium. 

All  the  transitions  from  the  fine  and  delicate  cilia 
to  the  large  cilia,  tapering  in  form  like  a  stilleto,  which 
have  been  called  cirri,  have  been  observed;  moreover 
these  cirri  are  formed  of  agglutinated  cilia;  by  the  aid 
of  certain  re-agents  they  have  been  dissociated. 

An  observation  of  a  ciliated  infusory,  the  Didinium 
nasutum  (see  the  illustration  further  on)  made  by  M. 
Balbiani,  shows  that  the  movement  of  the  cirri  is  not 
an  involuntary  movement  like  that  of  the  cilia  of  the 
vibratile  epithelium,  with  which  it  has  often  been 


OF  MICRO-ORGANISMS. 


ii 


compared,  but  that  it  is  completely  under  the  control 
of  the  will  of  the  animal,  like  the  organs  of  locomotion 
of  animals  much  higher  in  point  of  organization. 

"  The  Didinium  has  two  rows  of  equal,  and  rather 
strong,  vibratile  cilia,  disposed  transversely  around 
the  body,  in  the  form  of  two  belts  or  crowns.  The 
rest  of  the  body  of  this  animal  is  entirely  stripped  of 
cilia,  but  its  double  vibratory  belt  suffices  to  enable  it 
to  execute  the  most  rapid  and  most  varied  evolutions 
in  the  water.  Not  only  does  it  swim  forwards  and 
backwards  with  perfect  ease,  but  the  progression  in 
both  directions  is  always  accompanied  by  a  rapid  rota- 
tory movement  of  the  animal  about  its  longitudinal  axis, 
similar  to  that  observed  in  other  infusoria  that  have  a 
cylindrical  body.  The  two  rows  of  cilia  always  act  in 
union  during  the  locomotion,  and  the  direction  which 
the  animal  gives  to  them,  determines  the  direction  in 
which  it  wishes  to  move.  In  the  movement  for- 


Fig.  i. — Didinium  na- 
sutum  (Balbiani)  Fig- 
ure representing  move- 
ment forward. The  cilia 
are  all  turned  towards 
the  front  part  of  the 
body. 


Fig.  2. — Didinium  na- 
sututii  (Balbiani).  Out- 
line of  movement  back- 
wards. The  cilia  are 
all  turned  towards  the 
back  part  of  the  body. 


Fig.  3. — Didinium  na- 
sutum  (Balbiani).  A 
sketch  of  rotatory 
movement  in  one  spot. 
The  cilia  of  the  ante- 
rior belt  are  directed 
forwards,  while  those 
of  the  posterior  belt 
are  directed  backwards 

wards,  all  the  cilia  are  directed  toward  the  an- 
terior part  of  the  body  (fig.  i);  when  it  swims 
backwards,  they  are  reversed  (fig.  2).  The  in- 
fusory  thus  rapidly  makes  its  way  across  the  field  of 
vision  by  jerks;  from  time  to  time  it  suddenly  stops, 
all  the  time  continuing  to  turn  around  rapidly  on  its 


13  THE  PSYCHIC  LIFE 

axis  on  the  one  spot,  during  which  movement  the  cili- 
ated belts  beat  the  water  in  opposite  directions,  the 
anterior  ones  being  turned  forwards,  while  the  posterior 
are  turned  backwards  (fig.  3).  The  result  of  this  is 
that  the  effects  of  these  small  locomotive  apparatuses 
neutralize  each  other  in  the  same  manner  as  two  heli- 
ces acting  in  opposite  directions,  and  that  the  animal 
remains  stationary,  while  all  the  time  turning  rapidly 
about  itself,  sometimes  horizontally,  sometimes  verti- 
cally on  its  conical  appendage,  just  as  on  a  pivot." 

Certain  Infusoria,  for  example  the  Condylostoma 
patens,  which  has  been  thoroughly  studied  by  M. 
Maupas,  possess  at  the  same  time  the  two  kinds  of 
appendages,  the  cilia  and  the  cirri.  The  former,  which 
cover  the  dorsal  surface  of  the  animal,  are  fine,  very 
dense  and  animated  by  a  rapid  and  unceasing  vibra- 
tile  movement.  The  cirri,  which  cover  the  ventral 
surface  are  placed  apart;  furthermore  they  do  not  vi- 
brate rapidly;  their  movements  are  slow,  and  when 
the  infusory  moves,  one  can  see  them  move  success- 
ively on  the  plate  of  glass  and  support  themselves 
there,  in  the  manner  of  a  foot,  to  make  the  body  ad- 
vance. When  the  animal  stands  still,  the  cirri  are  ab- 
solutely immobile,  while  the  cilia  continue  their  vibra- 
tile  movement.  This  observation  which*  can  equally 
well  be  made  of  the  Oxytrichid,  shows  that  the  vibra- 
tile  cilia  are  the  organs  of  involuntary  movement,  and 
that  the  cirri  are  more  directly  subject  to  the  will. 
The  fact  is  demonstrated  by  the  experiments  of  Ross- 
bach,  who  observed  that,  under  the  influence  of  the 
falling  of  the  temperature  (from  +  15  to  4-  4)  or  of 
the  rising  of  the  temperature  (from  +  35  to  4-  40)  or 
under  the  influence  of  various  chemical  substances, 
the  large  cilia,  the  organs  of  voluntary  movement, are 


OF  MICR  O-  OR  GANISMS.  1 3 

paralysed,  while  the  fine  and  delicate  cilia  continue 
their  movements,  which  do  not  seem  to  be  under  the 
influence  of  the  will.  These  movements  alone  cause 
the  whole  body  to  rotate  until  the  vibratile  cilia  are 
in  their  turn  paralyzed. 

Besides  the  cilia  and  the  cirri,  other  appendages 
in  the  form  of  membranes  are  found  among  the  Infu- 
soria, appendages  which  are  attached  to  the  anterior 
part  of  the  body  or  the  peristome;  these  membranes 
serve  the  purpose  of  causing  eddies  in  the  water, 
which  bring  the  floating  alimentary  particles  into  the 
mouth.  They  are  modifications  of  the  vibratile  cilia; 
these  membranes  like  the  cirri  are  formed  of  aggluti- 
nated cilia. 

The  Flagellum.  The  study  of  the  third  organ  of  lo- 
comotion, the  flagellum,  brings  us  to  speak  of  the 
class  of  Mastigophores  and  more  particularly  of  the 
group  Flagellata.  The  Flagellates  are  Protozoa  of 
very  small  size,  all  in  all,  very  much  smaller  than  the 
ciliated  Infusoria.  They  have  no  vibratile  cilia  at  all, 
but  they  are  always  equipped  with  one  or  more  fila- 
mentous appendages  which  have  the  form  of  a  long 
lash.  This  is  the  flagellum.  This  lash,  like  all  the 
organs  of  locomotion  hitherto  studied,  has  two  func- 
tions: it  is  at  once  an  organ  of  locomotion  and  an 
organ  of  prehension.  The  flagellum  is  most  fre- 
quently single  or  double  (see  fig.  4,  representing  the 
Euglenadeses  with  its  single  flagellum);  sometimes  a 
person  can  count  a  much  larger  number  of  them,  four, 
six,  eight,  ten,  and  more.  As  regards  the  insertion, 
the  same  variations  are  met  with.  Sometimes  the 
flagella  are  very  numerous  and  seem  to  be  planted  on 
the  same  point  of  the  surface  of  the  body,  thus  forming 
a  brush  or  plume.  In  other  species  we  find  several 


THE  PSYCHIC  LIFE 


flagella  arising  in  the  anterior  extremity  of  the  body, 
directed  forwards,  and  also  posterior  or  caudal  fila- 
ments which  are  turned  toward  the  rear.  This  is 
observed  in  the  genus  Trichomonas;  the  anterior  fla- 
gella serve  for  purposes  of  locomotion,  perhaps  also 
for  the  prehension  of  food;  the  posterior  flagella,  on 
the  contrary,  are  solely  organs  of  loco- 
motion; they  resemble  a  trailing  tail 
and  perform  the  functions  of  a  rudder. 
In  passing  we  may  point  out  the 
e  great  morphological  resemblance  be- 
tween the  Flagellata  and  the  sperma- 
tozoa of  animals,  the  antherozoa  and 
the  zoospores  of  plants.  The  organs 
of  propulsion  in  these  beings  are  the 
same. 

The  Protozoan  with  its  flagellum 
executes  the  most  varied  movements, 
moving  first  in  one  direction,  then  in 
another,  and  in  different  planes;  some- 
times the  animal  curves  about  entirely; 
but  most  frequently,  when  he  uses  it 
as  an  organ  of  prehension,  he  extends 

V-'  it  its  whole  length  before  himself;   the 

basilar  part  remains  completely  immov- 
Fie  4-  able  and  rigid,  while  the  free  end  alone 

Euglenadeses.  -         .         .  ,    . 

executes  movements  destined  to  drive 

r.  c.  — •  contractile  re- 
servoir; *  -eye,  /.  fOO(j  to  the  mouth,  which  is  generally 

—  disk  of  the  para-  J 

myione;  ch.  -  chro-  situated  at  the  base  of  the   flagellum. 

matophores; «.  —  nu- 
cleus. Ehrenberg   gives   to  the  flagellum  the 

name  proboscis;  its  peculiar  mobility  renders  it  worthy 
of  this  name.  The  flagellum,  like  the  vibratile  cilium, 
is  an  expansion  of  the  protoplasm  through  the  envel- 
oping membrane.  M.  Certes  has  observed  a  Proto- 


OF  MICR  O-  OR  GANISMS.  1 5 

zoan,  the  flagellum  of  which  between  whiles  re-entered 
into  the  mass  of  the  body,  with  which  it  mingled;it 
was  replaced  by  a  pseudopod  which  soon  attenuated 
and  took  the  form  of  a  flagellum. 

Biitschli  has  recently  made  a  very  interesting  ob- 
servation on  this  organ  of  locomotion.  Under  certain 
circumstances,  the  Peridinia  (Dinoflagellates)  throw  off 
their  long  flagellum  and  enter  into  a  state  of  repose; 
they  generate  them  quite  as  easily.  In  the  Glenodin- 
ium  cinctum,  Biitschli  has  seen  the  flagellum  roll  itself 
up  first  like  a  cork-screw,  and  then  suddenly  detach 
itself  from  the  animal;  having  become  free,  it  stirs 
about  in  the  water  for  several  minutes  before  becom- 
ing motionless.  This  observation  enables  us  to  refute 
those  naturalists  who  believe  that  the  vibratile  cilium 
is  an  appendage  of  the  cuticle,  by  bringing  forward 
the  fact  that  when  the  cilia  with  the  portion  of  the  cu- 
ticle in  which  they  are  inserted  are  separated  from  the 
cell,  the  cilia  continue  to  move;  we  have  just  seen 
that  the  flagellum  moves  even  after  it  is  separated 
from  the  cuticle;  this  persistence  of  movement  is 
sufficiently  explained  by  the  protoplasmic  nature  of 
the  cilia  and  of  the  flagellum. 

From  another  point  of  view,  the  observation  of 
Biitschli  gives  us  a  curious  example  of  the  phe- 
nomena of  autotomy,  which  have  recently  been  studied 
by  Fredericq. 

The  pseudopodia,  the  vibratile  cilia,  and  the  flagel- 
lum, constitute  the  three  motor  organs  that  are  most 
frequently  found  in  the  kingdom  of  the  Protista. 
Among  the  Infusoria,  moreover,  particular  differentia- 
tions of  the  protoplasm  have  been  described,  which 
may  be  compared  to  the  muscular  fibres  of  the  higher 
animals.  The  Vorticellae  are  supported  by  contractile 


16  THE  PSYCHIC  LIFE 

peduncles.  These  are  filaments  capable  of  rolling 
themselves  up  into  the  form  of  a  cork-screw,  when  the 
animal  is  disturbed.  Certain  Infusoria  can  modify 
the  form  of  their  body  by  a  sudden  contraction:  they 
have  been  called  metabolic;  such  are  the  Stentors, 
the  Prorodons,  the  Spirostomes.  In  contradistinction, 
those  which  do  not  change  their  form,  for  example  the 
Paramecia,  have  been  called  ametabolic.  Accord- 
ing to  the  observations  of  Lieberkiihn,  which  date 
back  to  1857,  the  metabolic  Infusoria  have  their 
bodies  divided  into  large  granulous  bands,  separated 
by  bright  filaments.  It  has  been  asked  which  is  the 
contractile  element:  is  it  the  band,  or  is  it  the  fila- 
ment? Oscar  Schmidt,  Kolliker,  Stein,  and  Rouget 
think  that  it  is  the  band  which  is  the  contractile  ele- 
ment. This  opinion  is  based  on  the  following  fact, 
which  M.  Rouget  was  the  first  to  observe:  at  the  mo- 
ment at  which  the  animal  contracts,  the  band  presents 
transverse  striae;  this  appearance  is  due  to  the  fact 
that  the  bands  contain  in  the  state  of  rest  small  gran- 
ules which,  during  the  contraction  of  the  animal,  are 
disposed  in  transverse  series,  so  as  to  recall  the  sar- 
cous  elements  of  Bowman. 

Lieberkiihn,  Greef,  and  Engelmann  attribute  the 
active  part  to  the  bright  fibre.  Engelmann  has  based  his 
opinion  on  the  fact  that  he  recognized  in  the  filament 
the  property  of  double  refraction,  which,  according  to 
him,  belongs  to  all  contractile  substances,  while  the 
substance  which  separates  the  filaments  shows  only 
single  refraction. 

However  that  may  be,  it  is  one  of  these  two  ele- 
ments that  possesses  the  power  of  contraction,  and 
which  deserves  the  name  of  myophanc,  which  Haeckel 
gave  it.  It  is  very  remarkable  that  in  the  Stentors 


OF  MICRO-ORGANISMS.  17 

and  the  Spirostomes  the  fibrillous  striae  are  in  intimate 
connection  with  the  basilar  extremity  of  the  vibratile 
cilia.  In  the  Vorticellae  one  can  clearly  see  the  fibrils 
converge  toward  the  axis  of  the  style,  the  contractile 
element  of  which  they  constitute. 

We  shall  not  leave  the  study  of  the  motor  organs 
without  saying  a  word  about  the  rhythmical  movements 
which  can  be  seen  in  the  contractile  vesicle  of  the 
Micro-organisms,  vegetable  as  well  as  animal.  This 
vesicle  is  a  small  cavity  which  is  dug  into  the  proto- 
plasm, and  which  alternately  increases  and  diminishes 
its  capacity.  Scientists  by  no  means  agree  as  to  its  ex- 
act function;  Biitschli  and  Stein  consider  it  to  be  a 
secretive  apparatus.  Its  pulsations  are  very  regular. 
Their  number  is  constant  in  every  species.  In  the 
chilodon  cucullulus,  a  pulsation  occurs  every  two  sec- 
onds; in  the  Crytochium  nigricans,  every  three  sec- 
onds; in  the  Vorticellae,  every  eight  seconds;  in  the 
Euplotes,  every  twenty-eight  seconds;  in  the  Acineria 
tncurvata,  every  six  minutes;  Rossbach,  whose  curi- 
ous experiments  with  the  vibratile  cilia  and  the  cirri 
we  have  already  cited,  has  made  analogous  experi- 
ments with  the  contractile  vesicles.  He  observed  es- 
pecially that,  under  the  action  of  alkaloids,  the  con- 
tractile vesicle  ceased  pulsating  in  diastole,  and  di- 
lated enormously;  but  poisonous  agents  do  not  act 
all  at  once  on  the  movements  of  the  vesicle;  they  begin 
by  paralyzing  the  larger  cilia,  which  are  under  the  in- 
fluence of  the  will.  The  movements  of  the  vesicle, 
like  those  of  the  small  cilia,  persist  for  a  much  longer 
time.  M.  E.  Maupas  has  seen  Paramecia,  killed  by 
a  discharge  of  trichocysts,  become  completely  immo- 
bile, with  their  vibratile  cilia  inert  and  rigid, 
while  the  contractile  vesicle  continued  to  pulsate 


i8  THE  PSYCHIC  LIFE 

with  the  same  activity;  this  activity  continued  for  an 
hour. 

We  have  now  briefly  examined  the  morphology  of 
the  motor  organs  of  Micro-organisms. 

It  is  very  difficult  to  determine  the  physiological 
process  of  the  movements  produced  by  these  organs. 
The  simplest  movements  and  the  ones  most  easily  un- 
derstood, are  those  by  which  a  cell  suddenly  and 
strongly  irritated  withdraws  its  prolongations  and  as- 
sumes a  spherical  form;  this  change  of  form  can  be 
explained  by  a  quick  condensation  of  the  protoplasm, 
which  becomes  the  seat  of  a  phenomenon  similar  to 
that  of  a  contracting  muscle.  The  sudden  modifi- 
cations which  are  observed  to  take  place  in  the  form 
of  the  so-called  metabolic  Infusoria  are  in  this  way 
explained  by  an  analogous  phenomenon,  so  much  the 
more  evident  as  the  Infusoria  which  possess  this  prop- 
erty, show  in  the  cortical  layer  of  their  protoplasm 
(ectosarc)  granulous  bands  which  have  with  more  or 
less  justice  been  compared  to  the  muscles  of  the 
higher  animals.  The  displacements  of  the  body  de- 
termined by  the  pseudopodia,  by  the  vibratile  cilia, 
and  by  the  flagellum  are  much  more  difficult  to  inter- 
pret; meanwhile  it  is  probable  that  the  movement 
proceeds  from  the  contractions  of  the  protoplasm 
which  are  produced  either  in  the  ectosarc  or  in  the 
motor  organ  itself;  the  latter  is  automobile,  as  is  seen, 
for  example,  when  a  flagellum  separated  from  the  rest 
of  the  body  continues  to  move  in  the  liquid. 

It  is  well  known  that  any  number  of  discussions 
have  been  raised  as  to  the  manner  in  which  the  ped- 
icel on  which  the  Vorticellae  are  mounted,  contracts. 
Still  more  obscure  is  the  oscillatory  movement  of  the 
Bacteria.  These  small  beings  are  very  mobile  when 


OF  MICR  O-  OR  GANISMS.  19 

they  find  themselves  in  a  liquid;  they  frequently  ex- 
hibit a  movement  of  oscillation  which  sometimes  car- 
ries them  forward,  sometimes  backwards.  An  attempt 
has  been  made  to  explain  these  movements  by  postu- 
lating the  presence  of  organs  of  locomotion,  extremely 
slender  filaments  planted  at  one  of  the  extremities  of 
the  Bacteria  like  small  rods;  but  the  existence  of  these 
organs  has  not  been  absolutely  proved.  Even  more 
obscure  is  the  movement  observed  in  certain  Grega- 
rines.  It  would  seem  that  in  the  case  of  these  ani- 
mals, which  are  often  of  considerable  size,  one  ought 
to  be  able  to  understand  the  principle  of  their  move- 
ments much  more  easily  than  in  the  case  of  such 
small  beings  as  the  Bacteria;  but  this  is  not  the  case. 
The  Polycystids  have  a  very  peculiar  manner  of  mov- 
ing; the  motion  is  one  of  perfect  translation,  uniform 
and  rectilinear;  the  animal  seems  to  slide  all  of  a 
piece  over  the  object-plate;  it  can  go  to  the  right,  to 
the  left,  stay  its  motion  and  resume  it  again;  it  is  free 
in  directing  its  movements.  Now,  during  this  move- 
ment nothing  can  be  seen  to  take  place  in  the  body 
from  within  or  without.  An  analogous  phenomenon 
is  to  be  observed  in  the  Diatomes.  Some  scientists 
have  wished  to  explain  the  mysterious  motion  by 
translation  executed  by  the  Gregarines,  as  being  due 
to  an  imperceptible  undulation  of  the  sarcode;  but  if 
there  were  any  undulations  whatever,  one  ought  to  ob- 
serve a  correlative  movement  in  the  granules  inside; 
now  this  is  something  that  is  never  seen. 

Thus  there  still  exists  a  great  deal  of  obscurity 
concerning  the  principles  determining  motion  among 
the  Proto-organisms.  The  theories  based  upon  muscular 
contraction  that  have  been  propounded  from  observ- 
ing higher  animals,  are  by  no  means  sufficient  to  ex- 


20  THE  PSYCHIC  LIFE 

plain  the  phenomena  of  motility  among  certain  Pro- 
tozoa and  Protophytes. 

Nervous  System.  Hitherto  not  the  minutest  trace 
of  a  central  nervous  system  has  been  found  in  a  single 
Proto-organism.  The  nervous  function  among  these 
inferior  beings  devolves  upon  the  protoplasm,  which 
is  irritable,  which  feels  and  which  moves,  and  which, 
in  certain  species,  as  we  shall  see  later  on,  is  even  ca- 
pable of  performing  certain  psychic  acts,  the  com- 
plexity of  which  seems  quite  out  of  proportion  to  the 
small  quantity  of  ponderable  matter  which  serves  as 
a  substratum  to  these  phenomena.  There  is,  more- 
over, no  occasion  to  be  surprised  that  an  undifferen- 
tiated  mass  of  protoplasm  should  be  able  to  exercise 
the  functions  of  a  veritable  nervous  system.  In  fact 
every  nervous  element  is  nothing  else  than  the  pro- 
duct of  protoplasmic  differentiation;  the  protoplasm 
embodies  in  itself  all  the  functions  that,  in  conse- 
quence of  an  ulterior  division  of  labor  among  the 
pluricellular  organisms,  have  been  assigned  to  distinct 
elements. 

It  has  rightly  been  held,  therefore,  that  if  no  nerv- 
ous system,  anatomically  differentiated,  existed  in 
proto-organisms,  it  must  be  admitted  that  their  pro- 
toplasm contains  a  diffused  nervous  system.  Among  all 
the  observations  that  uphold  this  idea,  we  must  cite 
one  to  which  M.  Gruber,  a  professor  at  Freiburg,  in 
Breisgau,  has  recently  called  attention.  This  obser- 
vation was  made  on  a  large,  ciliated  Infusory,  the 
Stentor,  of  which  mention  will  be  made  so  often  here- 
after that  it  will  be  advantageous  to  give  a  full  de- 
scription of  it  beforehand. 

The  Stentor  has  an  elongated  body,  broadened  in 
front  like  a  funnel,  and  able  to  fasten  itself  by  its  pos- 


OF  MICR O-  OR GANISMS. 


21 


terior  extremity.  The  edge  of  its  peristome  is  covered 
by  a  belt  of  vibratile  cilia  disposed  about  a  spiral 
line.  The  mouth  occupies  the  most  sunken  part  of 
the  peristome. 

The  body  of  the  animal  is  striated  with  longitudi- 
nal bands;  at  the  plane  of  the  peristome,  these  bands 
take  a  different  direction:  they  become  transversal  and 
spiral.  In  the  interior  of  the  protoplasm  can  be  ob- 
served a  contractile  vacuole  and  a  nucleus  like  a  string 
of  beads,  made  up  of  a  large  number  of  grains.  This 
Infusory,  like  all  the  Ciliates,  mul- 
tiplies by  fission;  a  contraction  is 
seen  to  take  place  in  the  middle  of 
the  body;  the  segment  below  the 
contraction  generates  a  peristome 
similar  to  that  of  the  upper  seg- 
ment; then  a  second  contractile  vac- 
uole is  formed,  and  soon  the  two 
segments  represent  two  complete 
animals  which  possess  all  their  or- 
gans. Nevertheless,* the  two  Sten- 
tors  continue  to  be  united  for  a  cer- 
tain length  of  time  by  a  bridge  of 
matter,  located  even  with  the  point 
where  the  contraction  took  place; 
this  bridge  of  matter  gradually 
grows  thinner  and  thinner  and  be- 
comes as  fine  as  a  thread.  (See 
fig.  5.)  Now,  Gruber  has  observed 
that  the  two  Stentors  united  by  this  F'£- 
bridge  of  protoplasm  exhibit  perfect 
harmony  in  their  movements;  they  always  sway  in  the 
same  direction  at  the  same  time;  and  this  harmony  is 
necessary,  because  the  least  contrariety  of  motion 


Stentor  in    pro- 
cess of  division. 


22  THE  PSYCHIC  LIFE 

would  suffice  to  break  the  feeble  bond  that  unites 
them.  Moreover,  their  vibratile  cilia  beat  in  unison.  To 
explain  this  concordance  in  the  movements  of  the  two 
animals,  Gruber  assumes  that  the  entire  mass  of  their 
protoplasm  performs  the  function  of  a  diffused  nervous 
system,  which  has  the  effect  of  regulating  their  move- 
ments and  of  making  them  harmonize. 

We  might  add  that  the  Infusoria  possess  not  only 
a  diffused  nervous  system,  but  that  they  must  of  neces- 
sity possess  special  nerve  centres,  endowed  with  dif- 
ferent functions. 

It  will  be  remembered  in  fact  that,  under  the  influ- 
ence of  certain  poisonous  agents,  death  is  not  simultane- 
ous throughout  all  parts  of  the  organism.  What 
ceases  first  are  the  voluntary  movements  of  the  large 
cilia;  the  movements  of  the  small  cilia  are  able  to  per- 
sist much  longer;  and  finally,  when  all  the  cilia  have 
become  immobile  and  rigid,  the  vesicle  has  still  been 
seen  to  pulsate  for  an  hour.  This  gradual  death  re- 
calls what  we  remark  among  the  Vertebrates;  under 
the  influence  of  poisonous  agents,  the  brain  dies  first, 
then  follows  the  spinal  cord,  and  lastly  the  medulla, 
which  is  the  v/timum  nwriens. 

The  Organs  of  Sense.  All  the  Micro-organisms 
are  endowed  with  sensibility;  some,  like 'the  Infusoria, 
have  exceedingly  sensitive  powers.  But,  hitherto, 
organs  of  sense  anatomically  differentiated  have  been 
found  in  only  a  very  small  number  of  species.  Gen- 
erally, the  protoplasmic  expansions  which  we  have 
above  described  under  the  name  of  pseudopodia  are 
regarded  as  fulfilling  the  function  of  rudimentary 
organs  of  touch  which  advise  the  micro-organism  of 
the  presence  of  objects  which  happen  in  its  path;  but 
these  pseudopodia,  which  at  the  same  time  serve  as 


OF  MICRO-ORGANISMS.  23 

motor  apparatus,  do  not  exhibit  any  structure  which 
especially  fits  them  for  the  reception  of  sensory  im- 
pressions. Similarly,  Stein  considers  the  vibratile 
cilia  as  organs  of  touch.  As  these  are  organs  which 
have  not  undergone  any  differentiation,  we  shall  not 
stop  to  consider  them.  The  Infusoria  belonging  to 
the  genus  Cryptochilum  (Maupas)  carry  at  their  pos- 
terior extremity  a  long  rigid  bristle,  which  M.  Maupas 
regards  as  an  organ  of  touch,  intended  to  advise  the 
animal  of  the  approach  of  other  Infusoria. 

We  shall  speak  more  at  length  of  the  organ  of 
sight;  this  has  been  the  subject  of  numerous  treatises, 
some  of  which  are  quite  recent  and  of  the  greatest 
interest  to  general  physiology  and  psychology.  Of 
all  the  organs  of  sense  the  eye  is  the  one  which  is 
first  differentiated.  It  is  found  in  the  organisms  be- 
longing to  the  vegetable  kingdom  as  well  as  in  those 
belonging  to  the  animal  kingdom.  While  these  small 
beings  do  not  seem  to  possess  any  organ  especially 
adapted  by  its  structure  for  the  reception  of  tactile, 
olfactory,  or  gustatory  impressions,  a  large  number 
already  exhibit  an  ocular  spot,  that  is  to  say  a  differ- 
entiated organ,  for  the  purpose  of  sight  and  for  no 
other  purpose. 

Let  us  first  turn  our  attention  to  the  eye  of  the 
Protozoa. 

It  is  chiefly  in  the  group  of  Flagellates,  and  prin- 
cipally in  the  species  that  are  colored  green  by  chlo- 
rophyl  (for  example  the  Euglenae),  that  ocular  spots 
are  found;  these  spots  which  are  colored  a  bright  red, 
present  themselves  very  clearly  to  the  observation, 
for  they  are  set  off  by  the  uncolored  plasma  of 
the  anterior  part  of  the  body  where  they  are  generally 
located.  Oculiform  spots  are  also  found  in  the  species 


24  THE  PSYCHIC  LIFE 

colored  by  yellow  chlorophyl  ((Jroglena  volvox,  etc.). 
Generally,  there  is  only  one  spot,  situated  at  the  base 
of  the  flagellum.  This  is  seen  especially  in  the  Euglena 
viridis,  a  small  flagellate  infusory,  which  is  very 
abundant  in  fresh  waters,  which  it  often  covers  with 
a  thick  green  coating. 

In  the  Synura  uvella,  a  colony-forming  flagellate, 
there  exist  in  each  individual,  in  the  anterior  part  of 
the  body,  numerous  spots,  varying  from  two  to  ten. 

Below  we  give  an  illustration  representing  the 
anterior  extremity  of  the  Euglena  Ehrenbergii,  ac- 
cording to  Klebs.  A  large  ocular  spot  is  noticeable, 
in  contiguity  with  the  contractile  reservoir.  Ehren- 
berg,  deceived  by  the  appearance  of  these  two  or- 
gans, had  taken  the  contractile  reservoir  for  a  nerve 
ganglion. 

It  is  not  only   in    the   large 
group  of  Protozoans  that  the  red 
spots   are   met    with;    they    are 
found  also  among  the  vegetable 
Micro-organisms.     A  large  num- 
ber  of   green-colored  zoospores 
exhibit    at     the     anterior,    and  Fig_  6._Anterior  extremity  of 
usually   colorless,    extremity   of  SffifftSSWA 
their  bodies,  a  small  red  point  Ira«u7  vesicle.  V^.-coU- 
which  seems  to  have  exactly  the 

same  structure  as  the  red  spot  of  the  Euglenae.  It  was 
on  this  fact  that  Stein  based  his  opinion  that  the 
spot  of  Euglena  is  not  an  eye;  to  him  it  seemed  im- 
possible to  admit  that  the  vegetable  Proto-organisms 
could  possess  a  visual  organ.  This  is  an  excellent 
instance  of  a  priori  reasoning.  Later  on  we  shall 
see  that  Stein's  view  has  now  been  completely 
abandoned;  the  very  opposite  view  is  taken,  for  the 


OF  MICR  O-  OR  GANISMS.  25 

eye  of  the  Protista  is  considered  as  being  destined  to 
perform  chiefly  a  vegetable  function. 

Klebs  was  able  to  study  the  structure  of  the  ocular 
spots,  by  employing  a  very  ingenious  artifice.  When 
the  Euglenas  are  treated  with  a  solution  of  sea  salt,  in 
the  proportion  of  one  part  to  one  hundred,  an  enor- 
mous dilatation  of  the  contractile  vesicle,  which  forms 
a  hollow  in  the  protoplasm  of  the  animal,  is  induced; 
now,  as  the  red  spot  is,  so  to  speak,  glued  to  the  vesi- 
cle, it  undergoes  the  same  dilatation  as  the  latter  does, 
thus  greatly  facilitating  observation.  By  this  treat- 
ment it  has  been  observed  that  the  spot  is  a  small  dis- 
coid or  triangular  mass,  of  jagged  and  irregular  out- 
line; it  is  formed  of  two  material  parts;  for  a  base  it 
has  a  small  mass  of  reticulated  protoplasm,  and  in  the 
meshes  of  the  protoplasm  there  are  small  drops  of  an 
oily  substance,  colored  red. 

This  red  pigment,  which  has  received  the  name  of 
hematochrome,  is  not  without  its  analogy  with  the 
green  pigment  of  the  chlorophyl,  because  this  latter 
becomes  red  under  certain  conditions.  For  example, 
the  chlorophyl  pigment  which  fills  the  entire  body  of 
the  Hematococcus  pluinalis  becomes  red,  when  the 
animal  enters  into  a  state  of  rest;  the  stagnant  spores 
of  the  algae  also  assume  a  red  tint.  So,  also,  in  nu- 
merous plants,  the  parts  of  the  flower  destined  to  be- 
come red  are  green  as  long  as  they  are  enclosed  in 
the  bud.  It  is  thus  probable  that  the  red  pigment  of 
the  Euglenoids  is  derived  from  a  green  pigment. 

What  is  the  physiological  significance  of  these 
spots?  Ehrenberg  considered  them  as  eyes;  hence 
the  name  Euglena  (word  for  word,  pretty  eye),  which 
he  had  given  to  a  species  of  Flagellates  provided  with 
ocular  spots.  This  interpretation  had  been  questioned 


26  THE  PSYCHIC  LIFE 

by  all  the  authors  of  his  time,  especially  by  Dujardin. 
At  the  present  day,  however,  naturalists  have  come 
back  to  it,  in  consequence  of  observations  which  have 
been  made  on  other  Micro-organisms  that  possess  a 
more  perfectly  developed  eye. 

M.  Pouchet  has  discovered  in  the  Glenodinium 
Polyphemus,  which  belongs  to  the  group  of  Peridinia 
(or  Dinoflagellates,  according  to  the  classification  of 
Biitschli),  an  eye  about  the  function  of  which  there 
can  be  no  mistake. 

This  eye  occupies  a  fixed  place  in  the  cellule  of 
the  Peridinium;  it  has  a  uniform  location  and  position. 
It  consists  of  two  parts,  the  one  a  veritable  crystalline 
humor,  and  the  other  a  veritable  choroid.  The  cry- 
stalline is  a  strongly  refracting,  hyalin,  club-shaped 
body,  rounded  at  its  free  end,  which  is  always  directed 
forwards,  while  the  other  end  is  immersed  in  the  mass 
of  pigment  which  represents  the  choroid.  This  latter 
is  clearly  determined;  it  forms  a  sort  of  hemispherical 
cap,  enveloping  the  posterior  extremity  of  the  crys- 
talline. In  one  of  the  two  forms  of  Glenodinium  pol- 
yphemus,  the  choroid  pigment  is  red;  in  the  other  it  is 
black. 

M.  Pouchet  has  been  able  to  establish  that  in  the 
young  animals  the  crystalline  is  first  formed  of  six  to 
eight  refracting  globes,  which  are  merged  into  each 
other  in  order  finally  to  constitute  one  unified  mass. 
Also,  the  choroid  is  the  result  of  a  combination  of  the 
pigmentary  granules  which,  at  first  sparse,  group  to- 
gether and  finally  form  the  hemispheric  cap  that  covers 
the  posterior  extremity  of  the  crystalline. 

In  fact,  the  visual  organ  of  this  Peridinium  is  com- 
posed of  exactly  the  same  parts  as  the  eye  of  a  meta- 
zoon  with  one  exception,  the  absence  of  the  nerve 


OF  MICR  O-  OR  CAN  ISMS.  27 

element.  This  is  not  at  all  differentiated,  but  remains 
diffused,  like  the  whole  nervous  system.  M.  Pouchet 
calls  attention  to  the  interest  which  his  observation 
affords  from  a  taxonomic  point  of  view.  The  Peri- 
dinia  have  sometimes  been  classed  among  the  vege- 
tables; the  presence  of  starch  and  of  cellulose  in  their 
protoplasm  has  induced  Warming  to  classify  them 
among  the  Diatomaceae  and  Desmidiaceae.  It  is  ad- 
mitted to-day  that  certain  Peridinia  possess  an  eye, 
an  organ  which  has  hitherto  been  considered  as  the 
exclusive  attribute  of  animals.  Nothing  more  clearly 
emphasizes  the  altogether  artificial  character  of  the 
distinction  between  animals  and  vegetables  than  the 
results  of  dealing  with  Micro-organisms. 

Before  leaving  the  Peridinia,  we  would  remark 
that  these  small  beings  afford  an  interesting  fact  from 
the  point  of  view  of  the  history  of  the  Protozoa;  they 
are  provided  with  a  long  flagellum;  they  exhibit  in  ad- 
dition an  equatorial  line  on  which  formerly  a  crown 
of  vibratile  cilia  was  thought  to  be  recognizable:  this 
supposed  co-existence  of  a  flagellum  and  of  cilia  had 
determined  the  naturalists  to  form  a  group  of  Cilio- 
flagellates,  serving  as  a  transition  between  the  Fla- 
gellates, properly  so-called,  and  the  Ciliates.  Since 
then  it  has  been  discovered  that  the  Peridinia  do  not 
possess  vibratile  cilia;  what  had  given  rise  to  this  er- 
ror is  the  presence  of  a  second  flagellum  on  the  level 
of  the  transverse  line  which  we  have  just  described; 
the  movements  of  this  flagellum  have  the  appearance 
of  vibratile  cilia  in  motion. 

Some  time  before  the  investigations  of  M.  Pouchet, 
M.  Kiinstler  (of  Bordeaux)  had  discovered,  in  a  Fla- 
gellate of  the  genus  Phacus,  a  red  eye  which  is  also 
formed  of  two  parts;  it  is  composed  of  a  homogenous 


a8  THE  PSYCHIC  LIFE 

globule,  acting  as  a  crystalline  humor,  and  surrounded 
by  a  red  pigment,  acting  the  part  of  the  choroid. 

Before  M.  Kunstler,  Claparfcde  and  Lachmann, 
in  their  important  work  on  Infusoria  and  Rhizopods, 
had  described  a  similar  visual  organ  in  the  Freia  ele- 
gans,  a  ciliated  infusory  of  the  family  of  Stentorines. 
"  Immediately  behind  the  point  of  truncation,"  say 
they,  "  there  is  found  a  lunate  spot  of  intense  black, 
evidently  belonging  to  the  category  of  those  phenom- 
ena which  M.  Ehrenberg,  in  the  Ophryoglenae,  for  ex- 
ample, calls  an  eye  or  an  ocular  spot.  The  significance 
of  this  spot  has  never  been  known.  It  was  often  very 
much  denser  than  that  of  the  Ophryoglenae,  and  some- 
times there  was  discovered  behind  it  a  very  trans- 
parent corpuscle,  which  involuntarily  gave  rise  in  the 
mind  to  the  idea  of  a  crystalline  humor.  We  cannot, 
however,  add  much  of  importance  to  this  idea,  since 
the  functions  of  a  refracting  apparatus  must  neces- 
sarily remain  problematic,  as  long  as  we  do  not  dis- 
cover behind  it  a  nervous  apparatus  fitted  to  perceive 
the  impressions  received." 

This  last  conclusion  seems  to  us  excessively  cau- 
tious. The  co-existence  of  a  pigment  and  of  a  crys- 
talline humor  amply  suffices  to  characterize  a  visual 
organ.  As  to  the  nerve  apparatus  susceptible  of  per- 
ceiving impressions,  it  is  replaced  by  the  protoplasm, 
which,  as  is  well  known,  is  sensitive  to  light. 

Even  before  that,  in  1856,  Lieberkuhn  had  discov- 
ered in  a  ciliated  infusory,  the  Panophrys  flavicans, 
an  ocular  spot,  composed  of  a  convex  crystalline 
humor,  having  the  form  of  a  watch-crystal  enveloped 
by  pigment  and  placed  on  the  convex  side  of  the  oral 
fosse.  In  another  species,  the  Ophryoglena  atra,  he 
found  black  pigment,  but  no  crystalline  humor. 


OF  MICRO-ORGANISMS.  29 

It  is  impossible  to  believe  that  these  organs  are 
not  eyes,  for  they  have  the  same  structure  as  the  eyes 
of  comparatively  higher  classes  of  animals,  such  as 
certain  worms,  turbellaria,  rotifers,  lower-class  crusta- 
ceans, etc;  all  these  organs  are  similarly  formed  of  a 
small  crystalline  globule  enclosed  in  a  small  mass  of 
pigmentary  matter.  The  identity  of  structure  natur- 
ally leads  to  the  assumption  of  the  identity  of 
functions. 

The  eye  of  the  Euglena  is  the  simplest  of  all;  it 
is  even  reduced  to  the  maximum  point  of  simplicity, 
as  it  is  composed  of  a  spot  of  pigment.  What  induces 
us  to  believe  that  this  spot  is  a  visual  organ,  is  the 
presence  of  this  pigment.  In  fact  this  pigment  is 
found  in  the  most  elementary  visual  organs.  A  second 
argument  might  be  advanced;  the  red  pigment  of  the 
Euglena  exhibits  the  same  re-actions  as  the  coloring 
matter  that  fills  the  rods  of  the  retina  in  the  Verte- 
brates. From  among  these  re-actions  common  to 
both,  we  cite  the  decoloration  under  the  influence  of 
light  (Capranica). 

Whatever  the  case  may  be,  one  thing  is  certain, 
namely  that  the  Euglena  is  very  sensitive  to  the 
light.  When  they  are  kept  in  a  vessel,  they  are  in- 
variably seen  to  cover  the  side  exposed  to  the  light. 
M.  Engelmann  has  observed  that  light  acts  very 
strongly  upon  this  small  animal;  it  does  not  act 
directly  on  the  spot  of  pigment,  nor,  as  was  formerly 
thought,  on  the  flagellum,  but  on  the  protoplasm  which 
is  located  in  front  of  the  spot.  The  special  micro- 
spectral  object-glass  that  M.  Engelmann  constructed, 
enables  us  to  see  that  the  Euglens  always  congregate 
in  the  band  F  to  G  of  the  spectrum. 

So  far  as  the  vegetable  Micro-organisms  are  con- 


30  THE  PSYCHIC  LIFE 

cerned,  we  have  already  mentioned  that  a  large  num- 
ber of  the  algae  zoSspores  exhibit,  in  the  anterior  part 
of  their  body,  ocular  spots  of  a  beautiful  ruby  color: 
these  are  organs  that  probably  have  the  same  struc- 
ture as  the  red  spots  of  the  Euglenae.  Moreover,  it 
is  probable  that  certain  Microphytes  possess  more 
complex  visual  organs,  composed  of  red  pigment  and 
of  a  crystalline  humor.  M.  Balbiani  has  recently 
testified  to  this  fact  in  the  case  of  the  Pandorina  mo- 
rum,  a  spherical  colony  of  green  micro-organisms;  in 
each  colony  there  exists  a  certain  number  of  individ- 
uals which  possess  a  red  spot,  the  shape  of  which  is 
perfectly  circular;  if  this  spot  be  examined  under  a 
glass  of  very  high  magnifying  power,  one  can  readily 
see  that  it  is  formed  of  a  small  spherical  globule,  cov- 
ered, on  a  portion  of  its  surface,  by  a  cap  of  red 
matter.  This  observation  is  all  the  more  interesting 
because  it  is  made  on  a  being,  the  vegetable  nature  of 
which  is  to-day  no  longer  doubted;  the  Pandorina  are 
Volvocinae  which  modern  botanists  place  among  the 
algae.  (We  are  glad  to  give  our  readers  the  earliest 
communication  concerning  this  fact.) 

In  describing  the  eye  of  the  Protista,  we  said  that 
the  eye  is  the  only  organ  of  sense  which  is  distinctly 
differentiated  in  these  lower  beings.  But,  perhaps, 
this  assertion  is  too  sweeping.  Some  species  appear 
armed  with  small  organs  which  could  easily  be  in- 
vested with  a  sensory  function.  In  this  respect,  we 
may  cite  the  Loxodes  rostrum,  a  beautiful  ciliated  in- 
fusory,  remarkable  for  its  proboscis  and  for  the  mus- 
cular sheath  which  closes  its  mouth.  This  animal 
exhibits  along  the  dorsal  surface  a  row  of  small  organs 
which,  by  their  structure,  seem  destined  to  act  a  part 
in  performing  the  function  of  hearing.  They  are 


OF  MICR  O-  OR  G  AN  ISMS.  3 1 

formed  of  a  vesicle,  the  centre  of  which  is  occupied  by 
a  refracting  globule;  they  are  called  the  vesicles  of 
Miiller,  after  Johannes  Miiller,  who  discovered  them. 
The  auditory  organs  which  have  been  observed  in 
Worms  and  the  Coelenterata  are  apparently  composed 
of  a  vesiculiform  capsule  enclosing  a  solid  concretion, 
called  otolith.  Thus  it  is  possible  that  the  vesicles  of 
Miiller  may  be  auditory  vesicles.  Up  to  the  present 
time  this  organ  has  not  been  met  with  in  any  other 
species  of  Protozoa. 

ii. 

NUTRITION. 

After  studying  the  organs,  let  us  pass  to  a  study 
of  their  functions. 

It  is  not  our  intention  to  devote  special  chapters  to 
irritability,  instinct,  memory,  reasoning,  and  thepowers 
of  volition  in  Micro-organisms.  This  would  lead  to 
diffuseness  of  treatment.  Our  method  will  be  quite 
different.  We  shall  describe  as  a  whole  all  the  dif- 
ferent manifestations  of  psychical  activity  attendant 
upon  the  actions  of  Micro-organisms  in  the  exercise 
of  the  important  functions  of  their  existence.  The 
present  chapter  will  be  devoted  to  psychical  phe- 
nomena connected  with  the  act  of  nutrition. 

All  living  matter  possesses  the  power  of  continu- 
ally increasing  its  mass  by  the  inward  reception  of 
materials,  and  of  simultaneously  decreasing  the  same 
through  the  combustion  of  its  substance  with  the 
oxygen  of  the  atmosphere.  The  first  of  these  pro- 
cesses is  called  nutrition,  and  the  second,  respiration. 

We  shall  first  examine  the  psychical  phenomena 
which  precede  and  determine  the  act  of  respiration. 
These  phenomena  are  often  very  simple  and  of  little 


3a  THE  PSYCHIC  LIFE 

significance.  If  the  Micro-organism  lives  in  the 
water,  which  is  most  frequently  the  case,  the  oxygen 
contained  in  solution  therein  passes  directly  through 
the  cellular  cuticle  by  dialysis  and  comes  in  contact 
with  the  body  of  the  protoplasm;  in  which  case  the 
process  of  respiration  is  solely  a  chemical  phenome- 
non. But  it  may  happen  that  a  minute  organism 
chances  into  a  medium  containing  little  or  no  oxygen- 
gas;  amid  these  new  conditions  where  it  becomes  nec- 
essary to  move  towards  sources  emitting  oxygen  by 
voluntary  effort  and  directed  motion,  it  has  been  dis- 
covered that  a  great  number  of  Micro-organisms,  and 
particularly  Bacteria,  are  capable  of  detecting  the  ex- 
pansive power  exerted  by  oxygen  in  the  liquids  in 
which  they  are  found.  When  bacteria  of  putrefied 
matter  are  put  in  a  drop  of  water  containing  no  oxy- 
gen but  in  which  have  been  placed  chlorophyl  algae, 
or  green  Euglenae,  or  grains  of  chlorophyl  obtained  by 
crushing  green  cellules,  nothing  happens  in  the  first 
instant;  but  if  the  preparation  be  illuminated  so  as  to 
allow  the  chlorophyl  to  act,  the  bacteria  are  seen  to 
exhibit  very  rapid  movements  and  to  proceed,  al- 
together, towards  the  points  of  the  preparation  where 
the  generation  of  oxygen  is  taking  place,  that  is  to 
say,  about  the  grains  of  chlorophyl.  Under  these  con- 
ditions a  chemical  exchange  is  instituted  between  the 
chlorophyl  and  the  aerobious  Bacteria:  the  Bacteria 
disengage  carbonic  acid  gas  and  absorb  oxygen;  the 
chlorophyl  fastens  upon  the  carbon  of  the  acid  and 
sets  the  oxygen  at  liberty.  If  the  preparation  be 
darkened  the  Bacteria  cease  assembling  about  the 
chlorophyl  grains,  which,  hid  from  the  light,  cease  to 
disengage  oxygen.  The  clustering  begins  anew,  if  a 
ray  of  sunlight  is  again  let  touch  the  chlorophyl. 


OF  MICRO-ORGANISMS.  33 

Analogous  facts  have  been  observed  under  circum- 
stances somewhat  different.  In  a  preparation  from 
the  intestines  of  a  silk-worm,  M.  Balbiani  has  seen 
Bacteria  which  were  uniformly  distributed  throughout 
all  points  of  the  preparation,  gather  about  the  green 
and  undigested  cellules  of  the  leaves  contained  in  the 
intestines,  and  bury  themselves  in  them  as  if  to  par- 
take of  them.  In  other  instances,  the  same  naturalist 
has  observed  that  Bacteria  developed  in  a  drop  of 
silk-worm's  blood,  would  gather,  after  a  while,  about 
the  globules  of  the  blood;  undoubtedly  for  the  purpose 
of  seizing  the  oxygen  being  absorbed  by  them. 

Upon  the  basis  of  these  facts  M.  Engelmann  has 
established  the  method  called  the  Bacteria  method. 
He  regards  bacteria  as  a  living  reagent  which  enable 
us  to  reveal  the  trillionth  part  of  a  milligram  of  oxy- 
gen, that  is  to  say,  a  quantity  scarcely  greater,  accor- 
ding to  the  calculations  of  physicists,  than  a  molecule. 
This  curious  method  enables  us  to  explain  biological 
problems  which  had  hitherto  remained  unsolved. 
Before  this,  it  was  not  known  whether  the  colorless 
protoplasm  of  green  plants  could  or  could  not  disen- 
gage oxygen.  It  is  now  known,  thanks  to  the  bacte- 
ria, that  grains  of  chlorophyl  are  the  only  points  about 
which  the  liberation  of  oxygen  takes  place.  The  same 
method  has  enabled  us  to  prove,  in  the  variegated 
plants,  that  the  maximum  liberation  of  oxygen  coin- 
cides with  the  maximum  absorption  of  light.  Thus, 
in  the  case  of  green  algae,  the  red  and  the  violet  colors 
of  the  spectrum  are  the  spots  where  the  bacteria  ac- 
cumulate the  thickest;  consequently  here  is  where  the 
liberation  of  oxygen  is  greatest.  Now,  these  colors 
correspond  to  the  lines  of  greatest  absorption  in  the 
spectrum  of  chlorophyl.  In  the  case  of  brownish  yel- 


34  THE  PSYCHIC  LIFE 

low  cellules,  the  maximum  action  is  in  the  green;  in 
the  case  of  bluish  green  cellules,  in  the  yellow;  in  the 
case  of  red  cellules,  in  the  green.  The  author  has 
concluded  from  this  that  there  exists  a  series  of  col- 
oring substances  which,  like  chlorophyl,  have  the 
power  of  resolving  carbonic  acid  gas;  he  calls  them 
chromophyls.  In  the  same  way,  moreover,  this  method 
enables  us  to  solve  the  question  of  the  distribution  of 
energy  in  the  solar  spectrum.  As  M.  Engelmann  has 
remarked,  it  is  interesting  to  see  the  Bacteria  come  to 
confirm  our  theories  as  to  the  composition  of  solar 
light. 

Bacteria  are  not  the  only  organisms  that  eagerly 
make  towards  points  where  oxygen  is  to  be  found. 
A  large  number  of  other  Micro-organisms  act  in  the 
same  way  when  they  happen  into  a  medium  lacking 
oxygen.  M.  Ranvierhas  noticed  that  if  a  preparation 
containing  leucocytes,  screened  from  air,  be  examined 
for  a  certain  length  of  time  the  cellules  will  be  seen  to 
throw  out  long  filaments  towards  the  part  that  faces 
the  air-side  of  the  preparation.  It  appears,  then,  that 
a  rudimentary  oxygen-sense  exists  in  the  protoplasm 
of  Proto-organisms. 

This  sense  does  not  merely  apprise  .the  organism 
of  the  presence  of  oxygen;  it  enables  it,  further,  to 
gauge  the  tension  (expansive  power)  of  the  gas.  So 
that,  when  the  tension  becomes  too  powerful,  the  or- 
ganisms are  seen  to  flee  before  it. 

in. 

The  mode  of  nutrition  among  Micro-organisms  is 
not  uniform — a  fact  which  ought  not  to  appear  remark- 
able when  we  bear  in  mind  that  this  immense  group  is 
made  up  of  all  manner  of  heterogeneous  beings  that 


OF  MICR  O-  OR GANISMS.  35 

have  nothing  in  common  save  the  microscopic  little- 
ness of  their  bodies  and  the  simplicity  of  their 
structure.  Three  main  types  of  nutrition  may  be 
briefly  distinguished. 

i.  Vegetable  nutrition,  or  according  to  Biitschli's 
expression,  holophytic.  This  is  the  method  of  nutri- 
tion among  animal  or  vegetable  cellules  that  contain 
chlorophyl  and  that  nourish  themselves  by  forming 
organic  nutriment  from  ingredients  taken  from  the 
surrounding  medium.  It  is  hardly  necessary  to  call 
to  mind  that  the  function  of  chlorophyl  is  that  of  nu- 
trition and  not  of  respiration.  This  phenomenon  was 
formerly  termed  the  diurnal  respiration  of  plants.  The 
expression  involves  several  mistakes.  Enough  to  say 
that  vegetables  respire  as  animals  do,  by  uniting  with 
oxygen,  and  that  that  respiration  continues  the  same 
both  day  and  night.  The  function  of  chlorophyl  is  by 
no  means  respiration;  its  office  is  to  decompose  the 
carbonic  acid  gas  of  the  air  and  to  seize  the  carbon, 
which  serves  the  plant  in  forming  ternary  or  qua- 
ternary substances.  This  chemical  work  is  performed 
by  all  chlorophyl  organisms  when  influenced  by  the 
radiation  of  light. 

Chlorophyl  does  not  belong  exclusively  to  the  veg- 
etable kingdom.  A  large  number  of  animal  Micro- 
organisms are  colored  green  by  this  pigment;  they  are 
met  with  principally  in  the  important  group  of  Fla- 
gellates. Their  assimilative  organs,  which  are  like- 
wise found  in  all  green  plants,  bear  the  name  of  chro- 
matophores;  they  have  lately  formed  the  subject  of 
interesting  investigations. 

The  chromatophores  are  small  bodies  of  protoplasm 
which  are  distinguished  from  protoplasm  in  general 
by  their  having  assumed  an  individual  structure. 


36  THE  PSYCHIC  LIFE 

These  little  bodies,  which  in  the  vegetables  are  called 
leucites,  have  a  granular  and  reticulate  structure;  they 
are  impregnated  with  a  coloring  substance,  at  times 
green,  at  times  yellow,  and  at  times  brown,  as  the  case 
may  be;  in  fact,  several  coloring  substances  are 
present,  which,  by  intermixture  in  different  propor- 
tions, form  colors  of  many  varieties.  The  best  known, 
after  green  chlorophyl,  is  yellow  chlorophyl  or  diato- 
tnin.  The  latter  coloring  substance  can  be  absorbed 
by  alcohol. 

The  Euglenoididae,  the  Chlamydomonadidse,  and 
the  Volvocinae  exhibit  enormous  chromatophores.  In 
the  case  of  the  Euglenae,  the  chromatophores  are 
formed  of  small  discoid  plates;  they  are  situated  di- 
rectly under  the  cuticle,  so  that  the  light  can  act 
upon  them  (see  fig.  4).  In  certain  species  of  Flagel- 
lata,  they  are  exhibited  under  the  cuticle  in  the  form 
of  two  large  plates  which  envelop  the  protoplasm 
like  a  cuirass  formed  of  two  pieces.  The  Chlamydo- 
monadidae  and  the  Volvocinae  have  green  chromato- 
phores, disc-shaped,  and  very  small. 

In  the  centre  of  the  chromatophore  a  small  bright 
space  is  observed  which  was  formerly  thought  to 
be  filled  with  chlorophyl;  in  reality,  it  isva  minute  solid 
globule  which  shows  an  extremely  close  analogy  with 
the  substance  composing  nuclei,  or  nuclein.  It  ex- 
hibits the  same  chemical  reactions;  it  actively  absorbs 
coloring  matter  and  grows  extremely  brilliant  when 
treated  with  acids.  Schmitz  gives  this  little  body  the 
name  of  pyrenoid  (from  Trvptjv,  nucleus).  It  is  around 
the  pyrenoid,  and  probably  through  its  action,  that 
starch  forms;  it  is  deposited  in  grains  or  re-unites  in  a 
ring  about  the  pyrenoid,  a  fact  easily  ascertained  by 
coloring  them  with  iodine. 


OF  MICR O-  OR GANISMS.  37 

Production  of  starch  has  also  been  observed  in  the 
colorless  Flagellates,  as  for  instance  in  the  Polytoma 
uvella.  These  latter  do  not  have  chromatophores,  but 
Kunstler,  and  after  him  Fisch,  has  noticed  that  every 
grain  of  starch  is  attached  to  a  small  mass  of  colorless 
protoplasm  which  is  the  focus  of  formation  for  the 
grains.  This  is  precisely  what  happens  in  vegetable 
organisms  where  colorless  starch-leucites  are  found. 
This  little  mass  of  protoplasm  always  faces  the  hilum 
of  the  starch-grain. 

As  the  function  of  the  chromatophores  is  exercised 
only  when  subjected  to  the  influence  of  light,  it  fol- 
lows that  green  Micro-organisms  must  have  light  in 
order  to  nourish  themselves. 

A  quite  remarkable  fact  may  be  adduced  in  this 
connection.  On  examining  the  kingdom  of  Protozoans 
as  a  whole,  it  will  be  seen  that  a  striking  coincidence 
exists  between  the  presence  of  the  eye  and  the 
presence  of  the  chlorophyl  pigment.  Organisms  hav- 
ing an  ocular  spot  are  in  most  cases  provided  with 
the  chlorophyl  pigment,  or,  in  other  words,  nourish 
themselves  as  plants  do,  by  generating  starch  through 
the  action  of  light.  This  fact  proves  that  sensibility 
to  light  is  in  some  manner  dependent  upon  the 
chlorophyl  function.  If  Flagellates  possessing  chro- 
matophores, that  is  organs  generating  starch,  have 
ocular  spots  at  the  same  time,  it  is  because  these  ru- 
dimentary eyes  enable  them  to  find  their  way 
towards  the  light,  which  is  the  necessary  agent  of 
chlorophyl  action.  Accordingly,  all  Micro-organisms 
having  eyes  nourish  themselves  as  plants  do.  In  their 
case,  the  object  of  the  eye  is  to  direct  the  performance 
of  a  vegetable  function. 

It  is  interesting  to  note  in  this  connection  that  the 


38  THE  PSYCHIC  LIFE 

Euglenae  might  nourish  themselves  as  animals  do, 
for  they  have  a  mouth  and  a  digestive  apparatus. 
The  buccal,  or  oral,  aperture  opens  in  the  anterior  end 
at  the  base  of  the  flagellum,  and  is  connected  with  a 
short  gullet  or  esophagus  (see  fig.  6,  the  mouth  and 
gullet  of  an  Euglena).  Nevertheless,  the  Euglena  is 
never  seen  using  its  mouth  for  swallowing  alimentary 
particles.  A  quite  curious  problem  is  involved  here. 
If  it  is  true,  as  has  been  claimed,  that  it  is  the  function 
that  makes  the  organ,  how  do  we  explain  the  existence 
and  especially  the  genesis  of  this  digestive  apparatus 
which  performs  no  function? 

It  is  the  presence  of  chromatophores  that  prevents 
certain  Flagellates  from  feeding  like  animals;  so  much 
so  in  fact,  that  the  digestive  apparatus  performs  its 
functions  in  Flagellates  which  have  no  chromato- 
phores and  are  not  provided  with  chlorophyl  pigment, 
an  instance  of  which  is  seen  in  the  Peranema.  The 
Peranema  is,  further,  an  exceedingly  voracious  animal. 
We  must  note  also  that  the  Peranema  does  not  exhibit 
ocular  spots  like  the  green  Euglena;  and  moreover,  it 
has  no  need  of  such,  since  it  does  not  have  to  seek  the 
light  to  generate  starch.  All  these  phenomena  are 
interdependent. 

The  influence  exerted  by  light  upon  the  green 
organisms  of  both  kingdoms  has  been  ascertained 
by  different  scientists.  Light  at  a  certain  degree 
of  intensity  attracts  them,  and  at  a  greater  de- 
gree, repels  them.  Some  years  ago  M.  Strassburger 
conducted  a  series  of  connected  experiments  upon  the 
movements  of  green  spores  towards  light.  It  was  ob- 
served, here,  that  the  grains  of  pigment  in  the  in- 
terior of  the  cellules,  when  under  the  influence  of 


OF  MICR  O-  OR  GANISMS.  39 

solar  radiations,  executed   movements    and  set  out- 
wards in  all  directions. 

2.  Nutrition  by  endosmosis,  or  saprophytic.    The  or- 
ganism   nourishes    itself   by    absorbing    through    the 
whole  surface  of  its  body  liquids   containing   the  pro- 
ducts of  vegetable  or  animal   decomposition.     Sapro- 
phytic beings  are  found   in  putrid  waters   or  in  infu- 
sions.    This  manner  of  nutrition  may  be  considered, 
from  the  point  of  view  which  now  engages  us,  as  the 
most  simple  of  all;  it  probably  allows  of   a  search  for 
food,  but  it  is  certain  that  no  movements  are  involved 
which  are  designed  to  draw  the  food  into  any  possible 
digestive  apparatus. 

3.  There  is  now  a  last  mode  of  nutrition,  of  which 
we  shall  treat   in   minute  detail;   namely,   animal  nu- 
trition, where  the  Micro-organism  seizes  solid  alimen- 
tary particles  and  nourishes  itself  after  the  fashion  of 
an  animal,  whether   it  be  by  means  of   a  permanent 
mouth  or  by  means  of  an  adventitious  one,  improvised 
at  the  moment  of  need.     This  manner  of  nutrition  is 
the  process  employed  by  higher  animals.    Among  the 
lower  organisms,  it   is   met  with  in  most  of  the  In- 
fusoria, in   the   Sarcodines,   in   many  of  the  Mastig- 
ophores,  and  in  others.    Respecting  the  Micro-organ- 
isms belonging  to   the    vegetable   kingdom,  we  find 
nutrition    by    endosmosis    and    chlorophyl    nutrition; 
the  Protophytes   never  possess   a  mouth    and  never 
absorb  solid  foods. 

Animal  nutrition  requires  very  remarkable  psy- 
chological faculties  in  the  organism  practicing  it. 
These  manifestations  of  psychic  life,  the  progressive 
complexity  of  which  we  intend  to  trace  in  starting 
from  the  simplest  protozoic  forms  and  arriving  at  the 
higher — prove  that  these  animalcula  are  endowed  with 


40  THE  PSYCHIC  LIFE 

memory  and  volition.     We  shall   group  our  remarks 
under  the  two  following  heads: 

a.  The  choice  of  food;  and 

b.  The  movements  necessary  for  the  prehension  of 
food. 

The  Micro-organisms  do  not  nourish  themselves 
indiscriminately,  nor  do  they  feed  blindly  upon  every 
substance  that  chances  in  their  way.  Also,  when  they 
ingest  food  through  some  point  or  other  of  their  bodies, 
they  understand  perfectly  how  to  make  a  choice  of  the 
particles  they  wish  to  absorb.  This  choice  is  some- 
times quite  well  defined,  for  there  are  species  which 
feed  exclusively  upon  particular  foods.  Thus,  there 
are  herbivorous  Infusoria  and  carnivorous  Infusoria. 
Among  the  herbivorous  ones  may  be  classed  the  chilo- 
dons  which  feed  upon  small  Algae,  Diatomaceae,  and 
Oscillaria.  The  parmecia  live  principally  upon  Bac- 
teria. The  Leucophrys  is  a  specimen  of  the  carnivo- 
rous class;  it  devours  even  the  smaller  animals  of  its 
own  kind.  The  Cyrtostomum  leucas  eats  everything, 
as  do  the  Rotifers. 

Though  the  fact  of  an  exercise  of  choice  in  taking 
food  is  settled  beyond  question,  yet  the  interpreta- 
tion of  this  phenomenon  is  a  matter  of  much  uncer- 
tainty. Some  writers,  as  Charlton  Bastian  for  in- 
stance, explain  this  choice  of  food  as  an  affinity  of 
chemical  composition  existing  between  the  organism 
and  the  nutriment.  This  idea  does  not  lead  to  any- 
thing. Others  compare  the  discrimination  made  by 
the  Proto-organism  between  objects  presented  to  it, 
to  the  action  of  a  magnet  which  in  some  way  selects 
particles  of  iron  that  have  been  mixed  with  particles 
of  other  substances.  The  latter  interpretation  is  an 
evidence  of  the  tendency  evinced  by  some  naturalists, 


OF  MICRO-ORGANISMS.  41 

of  endeavoring  to  identify  the  attributes  of  living  or- 
ganic matter  with  the  physico-chemical  properties  of 
the  mineral  kingdom. 

In  our  opinion,  the  only  question  demanding  con- 
sideration is  whether  the  choice  of  food,  in  the  case 
of  Proto-organisms,  does  or  does  not  result  from  a 
psychical  operation,  similar,  for  example,  to  that  which 
takes  place  in  higher  organisms.  We  have  received 
a  noteworthy  communication  from  M.  E.  Maupas, 
upon  this  subject,  which  tends  to  establish  that  the 
choice  of  food  is  not  the  result  of  individual  taste  in 
the  Micro-organisms,  but  is  determined  by  the  or- 
ganic structure  of  their  buccal  apparatus  which  does 
not  allow  them  to  receive  other  forms  of  nutriment. 

We  must  closely  examine,  therefore,  the  mechan- 
ism for  prehension  of  food. 

The  following  is  what  occurs  when  the  Amoeba,  in 
its  rampant  course,  happens  to  meet  a  foreign  body. 
In  the  first  place,  if  the  foreign  particle  is  not  a  nutri- 
tive substance,  if  it  be  gravel  for  instance,  the  amceba 
does  not  ingest  it;  it  thrusts  it  back  with  its  pseudo- 
podia.  This  little  performance  is  very  significant;  for 
it  proves,  as  we  have  already  said,  that  this  micro- 
scopic cellule  in  some  manner  or  other  knows  how  to 
choose  and  distinguish  alimentary  substances  from 
inert  particles  of  sand.  If  the  foreign  substance  can 
serve  as  nutriment,  the  Amceba  engulfs  it  by  a  very 
simple  process.  Under  the  influence  of  the  irritation 
caused  by  the  foreign  particle,  the  soft  and  viscous 
protoplasm  of  the  Amceba  projects  itself  forwards  and 
spreads  about  the  alimentary  particle  somewhat  as  an 
ocean-wave  curves  and  breaks  upon  the  beach;  to 
carry  out  the  simile  that  so  well  represents  the  process, 
this  wave  of  protoplasm  retreats,  carrying  with  it  the 


4a  THE  PSYCHIC  LIFE 

foreign  body  which  it  has  encompassed.  It  is  in  this 
manner  that  the  food  is  enveloped  and  introduced  into 
the  protoplasm;  there  it  is  digested  and  assimilated, 
disappearing  slowly. 

There  are  cellules  found  in  the  inner  intestinal 
walls  of  lower  animals  which  effect  the  prehension  of 
solid  foods  in  the  same  manner  as  the  Amoeba  cellule: 
they  are  called  phagocytes. 

This  mode  of  prehension  is  beyond  contradiction 
the  most  simple  imaginable;  for  the  prehensile  organ 
is  not  as  yet  differentiated.  Every  part  of  the  proto- 
plasm may  be  made  to  serve  as  a  digestive  cavity  in 
enveloping  the  foreign  substance. 

From  the  special  standpoint  of  prehension  of  food, 
we  may  place  the  Actinophrys  sol  above  the  Amoeba. 
This  animalcule  is  a  small  microscopic  Ileliozolarian 
abounding  in  fresh-water  ooze.  It  casts  out  long, 
slender,  filamentous  pseudopodia  from  every  part  of 
its  body.  When  its  prey  or  any  alimentary  substance 
gets  into  the  midst  of  this  mass  of  filaments,  the  fila- 
ment affected  quickly  draws  back,  carrying  the  nutri- 
tive matter  with  it  towards  the  body  proper  of  the 
Actinophrys.  In  other  instances,  the  filaments,  anas- 
tomosing themselves,  form  a  sort  of  envelope  about  the 
prey.  At  the  instant  the  substance  comes  within  a 
short  distance  of  the  cellule,  a  part  of  the  protoplasm 
composing  the  mass  projects  itself  forwards,  and  en- 
compasses the  food,  which  is  carried  back  and  envel- 
oped in  the  midst  of  the  protoplasm  by  a  process  anal- 
ogous to  that  seen  in  Amoeba. 

In  the  case  of  the  Actinophrys  any  part  of  the  body 
could  serve  as  a  way  of  entry  for  food,  that  is  to  say, 
could  act  the  part  of  a  mouth.  To  use  the  expression 
of  W.  Saville  Kent,  it  is  a  pantostomate  being.  In 


OF  MICR O-  OR GANISMS.  43 

other  species  of  higher  organization,  this  mode  of  ali- 
mentation is  rendered  impossible  by  the  cutitcle  which 
encompasses  the  body;  the  formation  of  a  cuticle  im- 
pervious to  solid  foods  creates  the  necessity  of  a  buccal 
orifice  through  which  food  may  enter  into  the  interior 
of  the  protoplasm. 

A  curious  graduation  in  these  phenomena  is  noticed 
here.  Thus  there  are  organisms  destitute  of  a  per- 
manent and  pre-existing  mouth ;  their  mouth  is  im- 
provised as  the  occasion  demands,  is  adventitions,  so 
to  say,  and  the  reason  that  these  organisms  are 
ranked  higher  than  the  preceding  ones,  is  that  the 
mouth  is  invariably  formed  in  the  same  place. 

In  this  connection  we  may  examine  a  small  flagel- 
late Infusory  which  abounds  in  impure  waters,  the 
Monas  vulgarts.  It  carries  a  long  flagellum  attached 
to  its  anterior  extremity,  which  when  not  in  motion,  is 
coiled  up  against  the  body.  At  the  base  of  the  flagel- 
lum the  protoplasm  projects  a  pellucid  substance  in 
the  shape  of  a  lip.  This  protuberance  is  hollow, 
containing  a  vacuole  filled  with  liquid.  Cienkotvski 
has  described  how  these  different  organs  act.  The 
Bacteria  and  Micrococcus,  which  constitute  the  food 
of  the  Monas,  are  pulled  into  the  latter's  neighborhood 
by  strokes  of  the  flagellum;  at  that  instant,  the  animal 
becomes  conscious  of  the  proximity  of  these  other 
bodies,  for  the  protuberance  which  lies  at  the  base  of  the 
flagellum  extends  towards  the  corpuscule,  envelops  it 
in  its  own  substance,  and  pulls  it  back  into  the  interior 
of  the  Monad's  body.  Biitschli  has  made  an  analo- 
gous observation  with  the  Oikomonas  termo. 

The  prehension  of  food  comprehends,  here,  three 
phases,  in  two  of  which  the  organism  manifests 
psychical  activity :  first,  attraction  of  food  by  means 


44  THE  PSYCHIC  LIFE 

of  the  flagellum  ;  second,  formation  of  the  vesicle 
which  extends  towards  and  envelops  the  food,  when 
the  latter  has  come  near;  third,  absorption  of  the  food. 

The  Acinetae  are  organisms  that  move  about  very 
little  ;  they  frequently  remain  fixed  to  a  pedicle  their 
whole  life  long.  They  have  no  cilia,  but  exhibit  ra- 
diating prolongations,  more  or  less  numerous,  and 
sparse  or  grouped  in  tufts,  as  the  case  may  be.  These 
filaments  are  suckers,  provided  at  the  end  with  a  small 
air-hole.  When  a  thoughtless  Infusory  swims  into 
the  territory  of  an  Acineta,  the  latter  arrests  it  by  means 
of  its  stout  filaments  and  fastens  upon  the  former's  body 
the  cup-shaped  extremities  of  its  suckers,  which  make 
a  vacuum.  The  protoplasm  of  the  Ciliate  thus  cap- 
tured, slips  slowly  through  the  suckers  as  through 
tubes,  and  is  gathered  together  in  the  interior  of  the 
Acineta  in  the  form  of  small  drops.  In  the  Acinetae, 
accordingly,  particular  organs  are  adapted  to  the  pre- 
hension and  absorption  of  food.  Corresponding  to 
the  greater  complexity  of  physical  action,  the  psy- 
chical process  necessary  for  the  act  of  prehension  has 
likewise  become  more  complicated  than  is  the  case 
with  the  Amoeba.  The  Acineta  is  obliged  to  direct 
its  sucker  towards  the  Infusory  which, is  within  its 
reach,  and  consequently  the  animal  is  obliged  to  de- 
termine the  position  of  its  prey. 

There  are  Acinetidae  that  exhibit  prehensile  or- 
gans more  perfect  than  those  just  noticed.  Such  are 
the  Hemiophrys.  They  have  both  sucker  tentacles  and 
prehensile  tentacles.  The  latter  are  filaments  which 
the  animal  throws  about  its  victim  like  a  lasso,  thus 
enveloping  and  rendering  it  motionless,  while  it  pro- 
ceeds to  feed  upon  it  by  means  of  its  suctorial  ap- 
paratus. 


OF  MICR  O-  OR  CAN  ISMS.  45 

Now,  do  these  Acinetidae  show  any  preference  of 
choice  among  the  Infusoria  that  chance  to  fall 
within  reach  of  their  tentacles?  M.  Maupas,  who  has 
made  an  especial  study  of  these  organisms  had  at  first 
admitted  this  preference  in  choice.  But  he  afterwards 
rejected  the  notion.  In  1885,  he  writes  us:  "  I  find 
quite  another  explanation  of  the  impunity  with  which 
the  Coleps  hirtus  can  throw  itself  upon  the  terrible 
suckers  of  the  Podophrys  fixa.  The  stout  shell  with 
which  this  little  Infusory  is  enveloped,  serves  it  as  a 
shield  and  guards  it  from  the  deadly  grasp  of  the  Acine- 
tidae. The  Acinetidae  do  not  seize  the  Coleps  because 
of  any  dislike  of  the  latter,  but  because  they  are  un- 
able to  seize  them,  and  their  inability  results  from  the 
peculiar  structure  of  the  Coleps'  tegumentary  en- 
velope. The  Paramecia  which  also  escape  unscathed, 
are  similarly  provided  with  a  tegument  of  high  resist- 
ing power,  which  serves  them  as  a  protection  in  this 
contingency.  The  Stylonichia  histrio,  like  all  other 
Stylonichiae,  has  a  very  soft  tegumentary  envelope. 
They  are  accordingly  seized  and  devoured  by  the 
Acinetidae  without  difficulty.  The  detailed  knowledge 
of  the  differences  of  structure  in  the  tegumentary  en- 
velopes has  caused  me  to  abandon  the  idea  of  a  pre- 
ference or  dislike  in  the  choice  of  those  victims  which 
serve  as  food  for  the  Acinetidae.  Of  the  prey  that 
passes  by,  they  catch  what  they  can  and  not  what  they 
want  to." 

In  a  large  number  of  species  the  prehension  of  food 
is  preceeded  by  another  stage,  the  search  for  food, 
and  in  the  case  of  living  prey,  by  its  capture.  We 
shall  not  investigate  these  phenomena  among  all  the 
Protozoa,  but  shall  direct  our  attention  especially  to 
the  ciliated  Infusoria.  Their  habits  are  a  remarkable 


46  THE  PSYCHIC  LIFE 

study.  If  a  drop  of  water  containing  Infusoria  be 
placed  under  the  microscope,  organisms  are  seen 
swimming  rapidly  about  and  traversing  the  liquid 
medium  in  which  they  are  in  every  direction.  Their 
movements  are  not  simple;  the  Infusory  guides  itself 
while  swimming  about;  it  avoids  obstacles;  often  it 
undertakes  to  force  them  aside;  its  movements  seem 
to  be  designed  to  effect  an  end,  which  in  most  instances 
is  the  search  for  food;  it  approaches  certain  particles 
suspended  in  the  liquid,  it  feels  them  with  its  cilia,  it 
goes  away  and  returns,  all  the  while  describing  a  zig- 
zag course  similar  to  the  paths  of  captive  fish  in 
aquariums;  this  latter  comparison  naturally  occurs  to 
to  the  mind.  In  short,  the  act  of  locomotion  as  seen 
in  detached  Infusoria,  exhibits  all  the  marks  of  volun- 
tary movement. 

It  might  also  be  mentioned  that  every  species 
manifests  its  personality  in  its  mode  of  locomotion. 
Thus,  as  a  rule,  the  Actinotricha  saltans  when  placed 
in  a  preparation  where  it  finds  itself  at  ease,  remains 
for  a  few  moments  perfectly  immovable.  Then,  of  a 
sudden,  it  dashes  forward  with  the  rapidity  of  light- 
ning and  disappears  from  the  field  of  vision.  For  a 
time  it  darts  about  to  the  right  and  to  the  left,  and 
then  once  more  assumes  its  state  of  immobility.  It 
can  move  with  the  greatest  agility  through  masses  of 
debris,  in  the  midst  of  which,  bending  and  twisting,  it 
slips  about  with  wonderful  nimbleness.  The  Lagynus 
crassicolis,  on  the  other  hand,  moves  along  at  a  pace 
quite  constant  and  uniform,  neither  slow  nor  rapid. 
It  searches  about  among  algae  and  fragmentary  parti- 
cles. The  Peritromus  Emmce  moves  slowly.  It  runs 
lazily  over  the  Algae,  where  it  seeks  its  nutriment,  and 
does  not  stray  from  them  to  venture  into  the  open  water. 


OF  MICR  O-  OR  G AN  ISMS.  45 

Concerning  the  prehension  of  foods  and  the  search 
for  nutriment  on  the  part  of  Ciliates,  we  can  do  no  better 
than  to  quote  entire  a  note  which  M.  E.  Maupas  has 
been  pleased  to  send  us  upon  the  subject.  We  had 
put  to  him  two  questions:  First,  do  the  Ciliates  hunt 
their  food?  Second,  while  in  quest  of  live  prey,  do  the 
Ciliates  called  hunters  make  an  actual  hunt,  involving 
the  espial  of  prey  from  a  distance  and  the  voluntary 
pursuit  of  the  same  in  the  circuitous  paths  they  fol- 
low? M.  E.  Maupas  after  having  once  more  had  re- 
course to  observation,  briefly  recapitulates  his  opinion 
in  the  following  lines: 

"From  the  standpoint  of  prehension  of  food,  the 
Ciliates  may  be  divided  into  two  great  groups: 

1.  Ciliates  with  alimentary  vortices; 

2.  Hunter  Ciliates. 

"In  the  first  group  the  mouth  is  always  held  wide 
open,  and  along  with  the  nutritive  particles  which  the 
current  of  the  vortex  keeps  constantly  sucking  in,  we 
may  at  will  cause  other,  absolutely  inert  and  indigesti- 
ble, particles  to  take  the  same  course;  for  instance, 
such  substances  as  granules  of  carmine,  indigo,  and 
rice-starch.  These  granules,  totally  unfit  for  nutritive 
purposes,  pass  through  the  body  of  the  Ciliates  along 
with  the  genuine  nutriment  and  are  finally  cast  out 
intact  with  the  excrement.  I  think,  therefore,  we 
may  affirm  that  the  species  having  alimentary  vortices 
exercise  no  real  choice  in  selecting  their  foods,  and 
that  they  absorb  indiscriminately  all  corpuscules  which 
by  reason  of  their  form  and  density  admit  of  being 
seized  and  drawn  into  the  alimentary  whirlpool. 

"  In  the  case  of  the  hunter  Ciliates  proper,  the 
mouth  is  constantly  closed.  The  act  of  absorbing  each 
object  captured  is  accomplished  by  a  process  of  de- 


48  THE  PSYCHIC  LIFE 

glutition  comparable  in  every  phase  to  the  like  pro- 
cess in  higher  animals.  Furthermore,  these  species 
feed  only  upon  living  prey,  which  they  capture  and 
entrammel  by  means  of  their  trichocysts  (yid.  Archives 
de  Zoologie,  Vol.  I.  1883,  p.  607  and  ff.).  By  this  very  act 
they  exercise  a  choice  in  the  selection  of  food.  But 
this  manifestation  of  choice  is  not,  in  my  opinion,  the 
result  of  preference,  or  of  individual  taste,  but  is  the 
consequence  of  the  peculiar  construction  of  their  buc- 
cal  apparatus,  which  does  not  enable  them  to  take 
other  and  different  nourishment. 

"These  hunter  Infusoria  are  constantly  running 
about  in  quest  of  prey;  but  this  constant  pursuit  is 
not  directed  towards  one  object  any  more  than  an- 
other. They  move  rapidly  hither  and  thither,  chang- 
ing their  direction  every  moment,  with  the  part  of  the 
body  bearing  the  battery  of  trichocysts  held  in  ad- 
vance. When  chance  has  brought  them  in  contact 
with  a  victim,  they  let  fly  their  darts  and  crush  it;  at 
this  point  of  the  action  they  go  through  certain  manoeu- 
vres that  are  prompted  by  a  guiding  will.  It  very 
seldom  happens  that  the  shattered  victim  remains 
motionless  after  direct  collision  with  the  mouth  of  its 
assailant.  The  hunter,  accordingly,  slo'wly  makes  his 
way  about  the  scene  of  action,  turning  both  right  and 
left  in  search  of  his  lifeless  prey.  This  search  lasts  a 
minute  at  the  most,  after  which,  if  not  successful  in 
finding  his  victim,  he  starts  off  once  more  to  the  chase 
and  resumes  his  irregular  and  roving  course.  These 
hunters  have,  in  my  opinion,  no  sensory  organ  where- 
by they  are  enabled  to  determine  the  presence  of  prey 
at  a  distance;  it  is  only  by  unceasing  and  untiring 
peregrinations  both  day  and  night,  that  they  succeed 
in  providing  themselves  with  sustenance.  When  prey 


OF  MICRO-ORGANISMS.  49 

abounds,  the  collisions  are  frequent,  their  quest  profit- 
able, and  sustenance  easy;  when  scarce,  the  en- 
counters are  correspondingly  less  frequent,  the  ani- 
mal fasts  and  keeps  his  Lent.  The  Lagynus  crassicolis, 
accordingly,  never  sees  its  victim  from  a  distance  and 
in  no  case  directs  its  movements  more  towards  one 
object  of  prey  than  towards  another.  It  roams  about 
at  random,  now  to  the  right  and  now  to  the  left,  im- 
pelled merely  by  its  predatory  instinct — an  instinct 
developed  by  its  peculiar  organic  construction,  which 
dooms  it  to  this  incessant  vagrancy  to  satisfy  the  re- 
quirements of  alimentation. 

"The  vorticel  Infusoria,  when  in  a  medium  abound- 
ing in  food,  are  almost  entirely  sedentary  in  their 
habits,  only  making  slight  changes  of  position.  But 
if  they  are  placed  in  a  medium  affording  but  little  nu- 
tritive material,  they  become  as  migratory  as  the  hunt- 
ers, and  are  seen  to  race  about  in  all  directions  search- 
ing for  more  abundant  nutriment.  It  is  hard  to  find 
a  more  perfect  illustration  of  the  influence  exerted  by 
the  conditions  of  a  medium  upon  the  habits  and 
customs  of  animals. 

"The  Leucophrys patula  is  a  type  distinctively  car- 
nivorous and  possessed  of  an  extremely  voracious  ap- 
petite, a  fact  which  explains  its  power  of  multiplica- 
tion, one  of  the  greatest  I  have  studied.  With  a  tem- 
perature of  25°  in  my  laboratory  I  have  recently  seen 
it  separate  by  fission  seven  times  in  twenty-four  hours, 
that  is  to  say,  a  single  individual  produces  from  itself 
just  one  hundred  and  twenty  eight  others  in  that 
time.  In  constant  pursuit  of  its  prey,  it  seizes  its  vic- 
tims by  the  two  stout  vibratile  lips  with  which  its 
mouth  is  armed,  and  swallows  them  alive  and  whole. 
The  victims  may  be  seen  struggling  and  tossing  about 


for  a  time  in  the  interior  of  the  Leucophrys's  body 
and  afterwards  to  expire  slowly  under  the  action  of 
the  digestive  juices  of  the  vacuole  in  which  they  have 
been  enclosed.  Placed  in  a  medium  well-stocked  with 
small  Ciliates,  the  Leucophrys  have  their  bodies  con- 
stantly crammed  with  victims  swallowed  in  the  man- 
ner above  described.  Like  the  other  hunter  Ciliates 
the  Leucophrys  does  not  espy  its  victims  from  a  dis- 
tance and  does  not  guide  itself  towards  them.  It 
simply  darts  about  from  right  to  left,  every  moment 
changing  its  direction.  It  thus  increases  its  chances 
of  coming  in  collision  with  its  prey  and  every  time 
that  one  of  its  unfortunate  victims  falls  in  contact 
with  its  vibratile  lips,  it  is  seized,  irresistibly  drawn 
towards  the  mouth  and  swallowed  within  less  than  a 
tenth  of  a  minute." 

Certain  hunter  Infusoria  have  methods  of  pursuit 
and  capture  which  deserve  to  be  examined  separately. 
Claparede  and  Lachman  in  their  excellent  work  upon 
Infusoria  and  Rhizopods,  have  minutely  described  the 
manner  in  which  a  large  Infusory,  the  Amphileptus 
Meleagris,  attacks  the  Epistylis  plicatilis.  The  Epis- 
tylis  are  colonizing  vorticels  of  which  certain  individ- 
ual members  attain  a  size  of  not  less  fhan  0-21  mm. 
The  Epistylis  form  aborescent  groups,  the  ramifica- 
tions of  which  are  quite  regularly  dichotomous.  These 
ramifications  all  grow  at  exactly  the  same  rate  and  the 
individual  branches  all  rise  to  the  same  height,  rep- 
resenting what  is  called,  in  botany,  a  corymbous  in- 
florescence. "We  were  observing  one  day,"  says 
Claparede,  "in  the  hope  of  seeing  what  would  come 
of  the  manoeuvre,  an  Amphileptus,  which  was  slowly 
creeping  upon  a  colony  of  Epistylis.  The  way  in 
which  it  approached  the  Vorticels,  feeling  them,  so  to 


OF  MICR  O-  OR GANISMS.  5 1 

speak,  and  partly  enclosing  them  in  its  pliable  body, 
already  seemed  suspicious.  At  last,  it  made  a  direct 
attack  upon  one  of  them  by  fastening  itself  upon  the 
upper  part  of  its  body.  It  opened  its  huge  mouth, 
which  is  never  to  be  seen  except  when  the  animal  is 
eating,  and  slipped  over  the  Epistylis  like  the  finger 
of  a  glove  being  drawn  upon  a  finger  of  the  hand. 
We  saw  the  sides  of  the  buccal  aperture  (which  are 
capable  of  being  dilated  in  a  truly  astonishing  man- 
ner) slip  slowly  over  the  peristome  and  upon  the  body 
of  its  prey,  and  then  draw  together  about  the  point 
where  it  was  made  fast  to  the  pedicle.  The  cilia  cov- 
ering the  body  of  the  Amphileptus\)Q.gdj\  to  shake  with 
that  peculiar  motion  which  is  always  noticed  when  a 
ciliated  Infusory  secretes  a  cyst.  At  the  expiration  of 
a  moment  or  so,  a  fine  line  was  seen  to  appear  around 
the  whole  body  which  continued  to  spread  so  as 
soon  to  form  the  cyst."  (This  might  be  called  a  cyst 
of  digestion.)  "The  phenomenon  as  a  whole  is  quite 
simple.  An  Amphileptus  approaches  an  Epistylis 
devours  it  and  encysts  itself  upon  the  spot,  the 
victim  being  still  attached  to  its  pedicle.  It  then  en- 
deavors to  wrench  the  Epistylis  from  its  point  of  at- 
tachment by  twisting;  it  turns  on  its  axis  from  left  to 
right  and  then  from  right  to  left,  successively;  when 
it  has  succeeded,  it  continues  its  work  of  digestion, 
and  occasionally  divides  in  two  within  the  cyst  itself. 
During  the  last  stage  of  digestion,  it  rests  for  a  while, 
when  it  commences  again  to  turn  about  in  the  cyst, 
evidently  seeking  to  disengage  itself.  At  the  close  of 
a  certain  number  of  hours,  the  cyst  breaks.  The 
Amphileptus  issues  forth  and  starts  in  quest  of  another 
victim."* 


*  Etudes  sur  its  I'.tfusoires  et  les  Rhizopodes,  Vol.  II.  p.  166,  1861. 


5*  THE  PSYCHIC  LIFE 

The  hunter  Infusoria  are  frequently  armed  with 
trichocysts.  Trichocysts  are  urtical  filaments  which 
serve  the  animalcula  provided  with  them  to  disable  or 
wound  other  micro-organisms. 

A  large  unmber  of  Infusoria,  the  Paramccia,  the 
Ophryoglcna,  etc.,  use  their  trichocysts  as  organs  of 
defense.  With  other  species,  of  which  we  shall  speak 
more  at  length,  the  trichocysts  are  organs  of  offense. 
They  are  located  either  in  the  sides  of  the  mouth  or 
in  parts  adjacent  thereto;  this  is  the  case  with  the 
Lacrymaria,  the  Didinium,  the  Enchelys,  the  Lagynus, 
the  Loxophyllum,  and  the  Artiphileptus. 

These  latter  animalcula  attack  the  live  prey  that 
constitutes  their  food,  in  the  following  manner.  They 
dash  upon  their  victim  and  bury  the  trichocysts  with 
which  they  are  armed,  into  its  body.  The  victim  is 
immediately  brought  to  a  halt,  whereupon  the  hunter 
seizes  it  and  swallows  it.  So,  when  the  Lagynus  Elon- 
gatus  intends  to  seize  a  victim  that  has  fallen  into  its 
vortex  and  has  thus  been  drawn  into  the  neighbor- 
hood of  its  mouth,  it  throws  itself  swiftly  forward.  At 
the  moment  of  contact  the  hunted  Infusory  becomes 
suddenly  paralyzed  and  remains  perfectly  motionless. 
This  paralysis  is  evidently  caused  by  the  trichocysts 
which  line  the  aesophagus  of  the  Lagynus  and  with 
which  the  latter  has  transpierced  its  prey  at  the  mo- 
ment it  came  in  contact  by  its  anterior  extremity.* 

In  a  higher  stage  of  organization,  the  Microzoon 
possessing  a  mouth  changes  its  position  in  order  to 
intercept  its  prey,  and  give  it  chase. 

The  Didinium  Nasutum  (Stein),  a  carnivorous  In- 
fusory and  one  of  the  most  voracious  of  our  fresh  stag- 
nant waters,  operates  in  a  more  complicated  manner: 

•  Maupu,  op.  cit.,  p.  495. 


OF  MICRO-ORGANISMS. 


53 


it  casts  its  trichocysts  upon  its  victim  from  a  distance. 

The  importance  of  this  instance  induces  us  to  stop 

here  a  moment. 

The  Didinium  (fig.  7), 
as  regards  the  general 
shape  of  the  body,  may 
be  compared  to  a  dimin- 
utive cask,  rounded  off  at 
one  of  the  ends  and  term- 
inated at  the  opposite  ex- 
tremity by  an  almost  level 
surface  from  the  midst  of 
which  rises  a  conical  pro- 
jection quite  strongly 

Fig.  7.— Didinium  nasutum,  enlarged  marked.       This   projection 
two  hundred  diameters.   The  figure  rep-  .  ,  .    . 

resents  a  Didinium  overpowering  a  Pa-  IS  an  Organ  Of   deglutition 
ramefdum  aurelia.     The  nettle-like  fila- 

ments  discharged  by  the  Didinium  are  (swallowing)  J      a     longltU- 
seen   on   all   sides  of  the  Paramatcium;    ...  ...  . 

while  the  latter,   already  seized  by  the  dmal    StriatlOn    IS    noticed 
tongue-shaped  organ  of  the  Didinium,  is  ,  .  , 

being  gradually  drawn  towards  the  buc-  here      formed      OI      minute 
cal  orifice  (after  Balbiani).  . 

solid  rods,  of  extreme  ten- 
uity and  independent  of  the  sides.  These  organs 
are  the  weapons  used  by  the  Didinium  in  attacking 
the  live  prey  which  constitutes  its  sole  nourishment. 
Not  only  does  it  attack  and  devour  animalcula 
almost  as  large  as  itself,  but  frequently  it  even  seizes 
individuals  of  its  own  kind.  In  such  cases  it  is  always 
Infusoria,  and  never  the  Rotatoria,  although  the  latter 
often  abound  in  waters  which  the  Didinium  inhabits. 
It  appears,  moreover,  to  have  a  marked  predilection 
for  certain  species;  and  so  it  happens  that  the  huge 
and  inoffensive  Paramcecium  aurelia  is  almost  always 
its  choice  by  preference  among  the  animalcula  that 
inhabit  the  same  liquid.* 

*  The  Didinium,  Balbiani  tells  us,  never  attacks  the  Parmcecium  bursaria, 
which  is  distinguishable  from  the  P.  aurelia  by  its  green  coloration. 


54  THE  PSYCHIC  LIFE 

The  prehension  of  food  by  the  Didinium  exhibits 
interesting  aspects,  which  have  not  as  yet  been  ob- 
served in  any  other  Infusory.  M.  Balbiani,  in  his 
first  observations,  had  often  been  surprised  at  seeing 
animalcula  that  the  Didinium  had  passed  by  without 
touching,  suddenly  stop  as  if  violently  paralyzed; 
whereupon  our  carnivorous  specimen  straightway  ap- 
proached and  seized  them  with  seeming  facility. 
More  careful  examination  of  the  Didinium's  actions 
soon  furnished  the  key  to  this  enigma.  If,  while 
swiftly  turning  in  the  water,  the  Didinium  happens 
into  the  neighborhood  of  an  animalculum,  say  a  Para- 
mecium,  which  it  is  going  to  capture,  it  begins  by 
casting  at  it  a  quantity  of  bacillary  corpuscules  which 
constitute  its  pharyngeal  armature.  The  Parmecium 
immediately  stops  swimming,  and  shows  no  other 
sign  of  vitality  than  feebly  to  beat  the  water  with  its 
vibratile  cilia;  on  every  side  of  it  the  darts  lie  scat- 
tered that  were  used  to  strike  it.  Its  enemy  then  ap- 
proaches and  quickly  thrusts  forth  from  its  mouth  an 
organ  shaped  like  a  tongue,  relatively  long  and  re- 
sembling a  transparent  cylindrical  rod;  the  free,  ex- 
tended extremity  of  this  rod  it  fastens  upon  some  part 
of  the  Paramecium's  body.  The  latter  is  then  grad- 
ually brought  near  by  the  recession  of  this  tongue- 
shaped  organ  towards  the  buccal  aperture  of  the 
Didinium,  which  opens  wide,  assuming  the  shape  of 
a  vast  funnel  in  which  the  prey  is  swallowed  up.* 

Up  to  this  point  we  have  paid  little  attention  to 
movements  of  defence  and  of  flight.  Upon  this  sub- 
ject a  few  words  will  suffice.  When  vorticels  are 
alarmed,  they  are  seen  to  contract  forcibly  their  pedi- 


•  Arckirei  Je  toologit  txptrimttitalt,  1873,  Vol.  II.  p.  363.     Obstrv&tions  sur 
um  n.uutum,  by  E.  G.  Balbiani. 


OF  MICR  O-  OR  GANISMS.  5  5 

cle,  which  in  a  state  of  rest  stays  extended.  Infusoria 
placed  in  a  preparation  where  they  are  at  their  ease, 
swim  quietly  about;  if  any  sharp  excitation  disturb 
them,  they  accelerate  their  pace;  those  armed  with  a 
rigid  bristle  at  the  posterior  extremity,  rush  precipi- 
tately onward  whenever  another  Infusory  chances  to 
touch  that  tactile  appendage.  The  unaggressive  Par 
mecia,  when  attacked,  endeavor  to  escape,  but  are 
also  able  to  defend  themselves  by  means  of  the  tricho- 
cysts  with  which  their  ectosarc  is  armed. 

IV. 

Unicellular  organisms  do  not  all  live  in  a  detached 
state;  a  large  number  of  species  are  found  grouped 
together  in  colonies;  the  initial  basis  of  these  agglom- 
erations is  always  a  mother  cell,  the  offspring  of  which 
instead  of  dispersing  to  live  at  large,  remain  aggluti- 
nated to  one  another.  Ehrenberg  had  believed  that 
in  certain  species  (especially  in  the  case  of  the  Ant/io- 
physa  vegetans,  an  aggregation  of  minute  monads 
growing  as  a  sort  of  bush)  the  colony  was  created  by 
the  union  of  minute  organisms  that  originally  lived  at 
large;  but  observation  has  shown  that  his  theory  was 
incorrect.  It  may  be  laid  down  as  a  general  rule  that 
every  colony  of  monocellular  animals  or  vegetables 
spring  from  the  divisions  of  a  single  cellule.  The 
cellules  of  one  and  the  same  colony,  therefore,  are 
always  sister  cellules,  and  the  colony  represents  a 
family  in  miniature. 

A  leading  instance  of  a  colony  wholly  temporary, 
is  found  in  those  organisms  the  cuticle  of  which  does 
not  take  part  in  the  phenomena  attending  the  division 
of  the  protoplasm.  In  this  case,  the  protoplasm  beneath 
the  envelope  alone  divides;  the  segments  resulting 


56  THE  PSYCHIC  LIFE 

therefrom  are  often  numerous,  and  it  is  not  until  the 
plasma  has  finished  dividing  that  the  maternal  cuticle 
is  destroyed  and  that  the  segments  separate  to  live 
abroad  in  a  detached  state.  Up  to  that  time  they  re- 
main bound  together. 

It  is  thus  seen  that  the  existence  of  this  minute 
colony  is  a  transient  phenomenon,  which  lasts  only 
during  the  time  necessary  for  the  division  of  the  ma- 
ternal body.  These  phenomena  have  been  noticed 
among  many  of  the  Flagellates.  What  appears  surpris- 
ing is,  that  the  maternal  cellule,  although  continuing  to 
divide  beneath  the  envelope,  keeps  on  moving  about 
in  the  water  by  means  of  its  own  flagellum  as  if  still 
constituting  only  a  single  animal.  The  reason  of  this 
is  that  one  of  the  segments  into  which  the  plasm  is 
divided  and  which  is  situated  in  the  anterior  part  of 
the  mother-cellule,  remains  connected  with  the  flagel- 
lum and  takes  charge  of  its  movements.  This  seg- 
ment (like  an  individual  distinct  in  itself)  alone  guides 
the  bark  that  carries  its  sisters.  And  so,  although 
this  diminutive  colony  is  as  a  rule  but  short-lived,  a 
division  of  labor  has  been  effected  among  its  mem- 
bers; the  anterior  segment  is  alone  entrusted  with  the 
office  of  locomotion. 

The  colony  has  a  duration  less  ephemeral  in  the 
case  of  the  Goniutn  pcctorale,  a  Volvocine  known  in 
our  fresh  waters.  It  is  formed  by  the  aggregation  of 
sixteen  individuals  which  remain  detached  but  ad- 
here laterally  to  one  another.  The  colony  is  de- 
veloped in  one  way  only:  it  is  in  the  form  of  a  minute 
rectangular  plate  of  a  beautiful  green  color.  In  the 
case  of  the  Pandorina,  the  colony  assumes  the  form  of 
a  minute  sphere;  it  is  composed  of  sixteen,  or  as  many 
as  thirty-two  individuals,  joined  together  beneath  a 


OF  MICRO-ORGANISMS.  57 

stout  envelope;  each  member  remains  free  in  action, 
and  projects  its  two  flagella  through  the  cuticle. 
With  the  Eudoryna  elegans,  the  colony  is  modeled 
upon  nearly  the  same  plan  excepting  that  it  is  com- 
posed of  thirty-two  individuals  and  that  the  latter, 
placed  beneath  the  same  cuticle  at  equal  distances 
apart,  do  not  touch  one  another. 

In  the  genus  Volvox,  colonies  are  found  of  which 
the  structure  is  very  complicated.  Such  are  the  great 
green  balls  formed  by  the  aggregation  of  diminutive 
organisms,  which  form  the  surface  of  the  sphere,  and 
are  joined  together  by  their  envelopes;  they  have  each 
two  flagella,  which  pass  through  the  enclosing  mem- 
brane and  swing  unimpeded  on  the  outside;  the  en- 
velopes, each  tightly  holding  the  other,  form  hexag- 
onal figures  exactly  like  the  cells  of  a  honeycomb. 
Each  Volvox  is  at  liberty  within  its  own  envelope; 
but  it  projects  protoplasmic  extensions  which  pass 
through  its  cuticle  and  place  it  in  communication 
with  its  neighbor.  It  is  probable  that  these  proto- 
plasmic filaments  act  like  so  many  telegraphic  threads 
to  establish  a  network  of  communication  among  all 
the  individuals  of  the  same  colony;  it  is  necessary,  in 
fact,  that  these  diminutive  organisms  be  in  communi- 
cation with  each  other  in  order  that  their  flagella  may 
move  in  unison  and  that  the  entire  colony  may  act  as 
a  unit  and  in  obedience  to  a  single  impulse.  The 
number  of  micro-organisms  constituting  a  Volvox 
colony  is  quite  considerable:  as  many  as  12,000  have 
been  counted. 

It  was  upon  analogous  phenomena  that  Gruber 
based  the  existence  of  a  diffused  nervous  system  in 
the  Stentors.  The  same  line  of  reasoning  may  be  fol- 
lowed in  the  case  of  the  Volvox.  Since  unanimity  of 


58  THE  PSYCHIC  LIFE 

movement  is  demonstrable  among  twelve  thousand 
micro-organisms  constituting  a  colony,  it  must  be  in- 
ferred that  their  movements  are  regulated  by  the 
action  of  a  diffused  nervous  system  present  in  the 
protoplasm.  This  conclusion  is  all  the  more  inter- 
esting from  the  fact  that  these  Volvox  are  vegetable 
micro-organisms. 

In  the  dioecian  Volvox,  the  female  cellules  and  the 
male  cellules  are  joined  together  by  themselves  in  sep- 
arate colonies.  When  the  time  of  fecundation  arrives, 
the  male  cellules  or  antherozoids  scatter  and  proceed 
to  conjugate  with  the  female  cellules.  The  colony 
which  bears  the  female  cellules  also  contains  neutral 
cellules  which  are  not  designed  for  fecundation;  the 
latter  simply  perform  a  locomotive  function;  equipped 
with  one  eye  and  two  flagella,  they  are  intended  to 
move  the  great  colonial  ball:  they  are  the  oarsmen  of 
the  colony.  The  Volvox,  male,  female,  and  neutral, 
all  seek  the  light,  whether  solar  or  artificial,  and  settle 
near  the  surface  of  the  water.  As  soon  as  the  female 
colonies  have  been  fecundated,  the  oospores  change 
their  color:  they  turn  from  green  to  an  orange  yellow. 
At  this  point,  the  colony  is  seen  to  draw  away  from 
the  light  and  to  disappear  from  the  surface  of  the 
water.  This  change  of  position  is  effected  by  means 
of  the  vibratile  cilia  with  which  each  neutral  cell  is 
furnished  and  which  project  beyond  the  gelatinous 
sphere;  now,  as  no  change  of  color  or  form  is  noticed 
in  the  neutral  cells  after  fecundation,  it  may  be  asked 
from  what  cause  they  flee  from  the  light  which  they 
formerly  sought. 

Colonies  of  Proto-organisms  formed  by  the  division 
of  a  mother  cell  of  which  the  segments  remain  united, 
are  not  entirely  without  analogy  with  a  pluricellular 


OF  MICR  O-  OR  G  AN  ISMS.  59 

organism  which  likewise  springs  from  a  single  cell 
called  the  egg,  and  the  resultant  divisions  of  which 
do  not  separate. 

The  colony  constitutes  in  a  way  a  first  step  towards 
the  physiological  constitution  of  a  pluricellular  organ- 
ism; it  serves  to  fix  a  stage  of  transition  in  the  animal 
kingdom,  between  Protozoa  and  Metazoa.  A  fact  which 
strengthens  this  analogy  is,  that  certain  colonies,  as  the 
Synura  uvella  and  the  Uroglena  volvox,  can  divide  into 
two  other  colonies;  strangulation  acts  upon  the  mass 
just  as  if  upon  a  pluricellular  organism.  This  curious 
observation  was  made  by  Stein  and  Biitschli. 

Nevertheless,  an  essential  difference  still  separates 
the  Metazoa  and  the  Protozoan  colonies,  even  when 
in  these  colonies  a  division  of  function  has  been 
established  among  several  individual  groups.  The 
physiological  differentiation  brought  about  in  these 
Protozoan  colonies  is  the  result  of  a  mechanism  which 
differs  in  every  respect  from  that  by  which  it  is 
effected  in  the  case  of  the  Metazoans.  In  the  latter 
instance  the  differentiation  results  from  the  division  of 
the  embryo  into  germinative  folia  each  of  which  is  the 
origin  of  a  separate  group  of  organs.  At  a  certain 
stage  of  development,  the  superposition  of  these  folia 
gives  rise  to  the  formation  of  a  gastrula;  the  gastrula 
is  formed  by  two  folia  joined  together,  representing  a 
pouch  open  to  the  outside;  it  is  characteristic  of  Met- 
azoans, the  Protozoan  never  reaching  this  stage.  Cer- 
tain colonies  observed  by  Haeckel,  the  Magosphcera plan- 
ula  for  example,  and  the  volvox,  of  which  we  have  before 
spoken,  appear  in  the  form  of  a  sphere;  they  suggest 
an  anterior  stage  of  development  to  which  the  name  of 
morula  or  of  blastula  has  been  given;  but  they  do  not 
get  beyond  this  stage. 


60  THE  PSYCHIC  LIFE 

We  have  now  considered  assemblages  of  organ- 
isms which  live  joined  together  like  the  Gonium  and 
sometimes  united  by  a  material  band  like  the  Volvox, 
where  the  individuals  are  grouped  together  under 
one  and  the  same  cuticle.  Voluntary  and  free  combi- 
nations are  much  more  rarely  met  with;  nevertheless 
cases  occur.  There  exist  organisms  which  lead  a  life 
of  habitual  isolation  but  which  understand  how  to  unite 
for  the  purpose  of  attacking  prey  at  the  desired 
time,  thus  profiting  by  the  superiority  which  numbers 
give. 

The  Bodo  caudatus  is  a  voracious  Flagellate  pos- 
sessed of  extraordinary  audacity;  it  combines  in  troops 
to  attack  animalcula  one  hundred  times  as  large  as 
itself,  as  the  Colpods  for  instance,  which  are  veritable 
giants  when  placed  alongside  of  the  Bodo.  Like  a  horse 
attacked  by  a  pack  of  wolves,  the  Colpod  is  soon  ren- 
dered powerless;  twenty,  thirty,  forty  Bodos  throw 
themselves  upon  him,  eviscerate  and  devour  him  com- 
pletely (Stein). 

All  these  facts  are  of  primary  importance  and  in- 
terest, but  it  is  plain  that  their  interpretation  presents 
difficulties.  It  may  be  asked  whether  the  Bodos  com- 
bine designedly  in  groups  of  ten  or  twenty,  understand- 
ing that  they  are  more  powerful  when  united  than 
when  divided.  But  it  is  more  probable  that  voluntary 
combinations  for  purposes  of  attack  do  not  take  place 
among  these  organisms;  that  would  be  to  grant  them 
a  high  mental  capacity.  We  may  more  readily  admit 
that  the  meeting  of  a  number  of  Bodos  happens  by 
chance;  when  one  of  them  begins  an  attack  upon  a 
Colpod,  the  other  animalcula  lurking  in  the  vicinity 
dash  into  tne  combat  to  profit  by  a  favorable  opportu- 
nity. 


OF  MICR  O-  OR GANISMS.  6 1 

v. 

It  is  difficult  in  the  extreme  to  mark  out  the  lines 
of  a  psychology  of  Proto-organisms  from  data  so  in- 
complete as  those  we  have  just  collected.  We  shall 
content  ourselves  with  a  few  brief  considerations. 

The  apparent  result  of  our  investigations  up  to  this 
point  is,  that  the  greater  number  of  movements  and 
actions  observed  in  Micro-organisms  are  direct  re- 
sponses to  excitations  emanating  from  the  medium  in 
which  they  live.  It  is  the  condition  of  the  medium  that, 
to  all  appearance,  rigidly  determines  the  character  and 
manner  of  their  activity;  in  a  word,  they  exhibit  no 
marks  of  pre-adaptation. 

But  it  will  not  do  to  let  the  matter  rest  with  this 
general  survey  of  the  subject;  we  shall  have  to  examine 
more  closely  each  detail  of  these  reflex  actions  of  adap- 
tation, beginning  with  the  sensory  phase  and  ending 
with  the  motory  phase.  Analysis  discloses  that  sev- 
eral determining  elements  may  be  distinguished  in 
these  phenomena;  they  are: 

1.  The  perception  of  the  external  object; 

2.  The  choice  made  between  a  number  of  objects; 

3.  The  perception  of  their  position  in  space; 

4.  Movements  calculated,  either  to  approach  the 
body  and  seize  it,  or  to  flee  from  it. 

We  are  not  in  a  position  to  determine  whether  these 
various  acts  are  accompanied  by  consciousness  or 
whether  they  follow  as  simple  physiological  processes. 
This  question  we  are  obliged,  for  the  present,  to  forego. 

I.  The  perception  of  an  external  body.  Among  the 
lowest  forms,  it  appears  that  perception  is  always  the 
result  of  a  direct  irritation  produced  by  contact  of  the 
external  body  with  the  protoplasm  of  the  animalcule. 
This  is  what  takes  place,  to  all  appearance,  among  the 


62  THE  PSYCHIC  LIFE 

Amoebae;  for  these  organisms,  the  condition  necessary 
to  the  perception  of  a  solid  particle  is  contact  with  it. 
A  step  forward  has  been  effected  in  those  organisms 
that  are  able  to  perceive  external  objects  by  contact 
from  a  distance,  as  is  observed  for  instance  in  the 
Actinophrys,  which  perceives  all  bodies  that  chance  to 
touch  its  long  filamentous  pseudopods;  yet,  in  this  in- 
stance, the  pseudopod  merely  acts  the  part  of  an  ex- 
tended tactile  organ.  The  vibratile  cilia,  and  still 
more  the  long  lash  of  the  Mastigophores,  enable  the 
animal  to  discern  the  presence  of  contiguous  particles 
at  a  certain  distance  from  its  body,  by  the  pressure 
exerted  upon  their  appendages.  It  is  not  known 
whether  there  are  many  animalcula  that  perceive  the 
presence  of  nutriment  from  a  distance  and  without 
coming  in  direct  contact  with  it;  it  appears,  however, 
that  this  is  the  case  with  the  Didinium  which  shatters 
its  prey  from  a  distance  and  without  touching  it. 

2.  Choice.  We  have  seen  that  Micro-organisms  do 
not  absorb  indiscriminately  every  solid  particle  they 
meet.  They  exercise  a  choice.  Among  the  lower  spe- 
cies, the  choice  is  in  the  lowest  degree  rudimentary; 
the  organism  restricts  itself  to  a  discrimination  of 
mineral  particles,  sand  for  example,  from  organic  sub- 
stances; it  rejects  the  former  and  absorbs  the  latter. 
Among  the  higher  animalcula  the  choice  is  more  in- 
telligent. There  are  Infusoria  that  feed  only  upon 
plants  and  animals.  There  are  also  those  which  feed 
exclusively  upon  one  species. 

This  exercise  of  choice  is  one  of  the  most  incom- 
prehensible of  phenomena;  it  is  exceedingly  difficult 
to  explain  it  without  resort  to  anthropomorphism.  If 
we  hold  to  what  observation  directly  teaches  us,  the 
choice  may  be  said  to  consist  in  the  following  acts: 


OF  MICR  O-  OR GANISMS.  63 

when  the  animalcule  perceives  certain  kinds  of  sub- 
stances and  particularly  those  substances  which  serve 
it  as  customary  food,  it  invariably  goes  through  the 
same  movement,  which  consists  of  an  act  of  prehension; 
when  the  substance  touched,  seen,  or  collided  with, 
as  the  case  may  be,  is  of  another  kind,  the  Micro-or- 
ganism does  not  go  through  this  act.  Such  is  the 
phenomenon;  as  to  the  explanation  of  the  same,  we 
are  unable  to  give  one. 

According  to  M.  E,  Maupas,  if  certain  Infusoria 
feed  exclusively  upon  a  certain  species,  it  is  because 
their  buccal  apparatus,  or  organ  of  prehension,  makes 
it  impossible  for  them  to  feed  upon  different  species 
which  possess  different  tegumentary  envelopes.  The 
question  is  to  ascertain  whether  this  explanation  is 
applicable  only  in  certain  cases,  as  appears  very  prob- 
able to  us,  or  whether,  on  the  other  hand,  it  is  of  com- 
plete and  universal  applicability.  We  confess  that 
the  hypothesis  of  M.  Maupas  does  not  explain  to  us 
why  a  hunter  Infusory  that  throws  trichocysts,  like 
the  Didinium,  attacks  the  Paramaciuni  aurelia  and  not 
the  Paramcecium  bursaria. 

It  is  possible  that  certain  species  attract  the  or- 
ganisms which  feed  upon  them,  by  means  of  a  phys- 
ical or  chemical  excitation. 

The  researches  of  Prof.  Pfeffer,  of  the  Tubingen 
Botanical  Institute,  lend  a  certain  confirmation  to  this 
hypothesis. 

3.  Calculation  of  the  position  occupied  by  the  exter- 
nal body.  It  is  a  universal  fact  that  Micro-organisms 
not  only  perceive  external  bodies,  but  that  they  also 
indicate,  by  their  movements,  an  exact  knowledge  of 
the  position  occupied  by  these  bodies.  It  might  be 
said  that  they  invariably  possess  a  sense  of  position  in 


64  THE  PSYCHIC  LIFE 

space.  The  possession  of  this  sense  is  absolutely  in- 
dispensable to  them,  for  it  does  not  suffice  them  to 
know  of  the  presence  of  an  exterior  body  in  order  to 
approach  it  and  seize  it;  they  must  furthermore  know 
its  position,  so  as  to  direct  their  movements  accord- 
ingly. 

The  simplest  form  of  a  sense  of  localization  is  met 
with  in  the  Amoeba,  which,  when  it  closes  about  a  nu- 
tritive particle,  always  emits  its  pseudopods  at  pre- 
cisely that  part  of  its  body  where  the  foreign  substance 
caused  the  irritation.  The  most  complicated  instance  of 
localization  is  met  with  in  the  Didinium,  which  we  have 
so  often  cited;  the  Didinium  knows  precisely  the  po- 
sition of  the  prey  it  follows,  for  it  takes  aim  at  the  ob- 
ject of  its  pursuit  like  a  marksman,  and  transpierces  it 
with  its  nettle-like  darts.  Between  these  two  species, 
we  find  all  the  intermediate  instances  of  a  localization 
of  perceptions. 

However,  doubts  exist  upon  the  question  as  to 
whether  Proto-organisms  know  the  direction  and  dis- 
tance of  external  bodies,  or  whether  they  only  succeed 
in  getting  at  them  after  a  series  of  tentative  move- 
ments. The  observations  which  we  have  collated  do 
not  solve  the  question. 

4.  Motory  phase. — We  now  pass  to  the  motory 
phase.  The  movements  made  by  Micro-organisms  as 
if  in  response  to  an  excitation,  are  not  in  most  in- 
stances simple  reflex  motions;  they  are  movements 
adapted  to  an  end.  We  cannot  repeat  it  too  much: 
these  movements  are  not  explained  by  the  simple  phe- 
nomenon of  cellular  irritability. 

In  the  very  first  instance,  they  vary  according  to 
the  excitation;  a  given  excitation  produces  a  corre- 
sponding motory  response;  a  body  situated  at  the  right 


OF  MICR  O-  OR  GANISMS.  65 

does  not  bring  about  the  same  movement  that  a  body 
situated  at  the  left  does;  a  particle  of  the  nutritive 
sort  does  not  provoke  the  same  course  of  action  that 
a  particle  of  a  different  sort  does.  All  this  implies 
that  associations  have  been  established  in  the  proto- 
plasm between  certain  excitations  and  certain  move- 
ments. The  explanation  of  the  physical  nature  of 
these  association  appears  to  us  totally  impossible. 

The  quite  ingenious  ideas  broached  by  Spencer 
upon  the  lines  of  least  resistance  offered  by  the  com- 
misural  fibres  cannot  be  applied  here,  since  everything 
takes  place  in  a  single  cell.  What  would  be  necessary 
to  explain  is  how  and  in  consequence  of  what  mechan- 
ism of  structure  one  form  of  molecular  movement,  cor- 
responding to  a  given  excitation,  is  followed  by  a  cer- 
tain other  form  of  molecular  movement  correspond- 
ing to  an  act  likewise  determined. 

VI. 

FECUNDATION. 

We  now  enter  upon  a  subject  fraught  with  obscu- 
rity. We  shall  limit  our  investigations  to  ciliated  In- 
fusoria, as  it  is  among  these  species  that  fecundation 
and  the  psychical  phenomena  attendant  thereon  have 
been  best  observed. 

Ehrenberg  had  established  by  his  authority  the  pre- 
vailing opinion  in  science  that  copulation  never  takes 
place  among  Infusoria,  and  that  all  facts  observed  by 
early  writers  as  connected  therewith  are  to  be  re- 
garded as  phenomena  of  longitudinal  fissiparity.  This 
erroneous  idea  prevailed  unquestioned  until  1858, 
when  M.  Balbiani  addressed  a  communication  to  the 
Academy  of  Sciences,  wherein  he  showed  that  sexual 


66  THE  PSYCHIC  LIFE 

reproduction,  preceded  by  copulation,  is  found  among 
Infusoria. 

Before  entering  upon  a  description  of  the  changes 
that  take  place  in  the  nucleus  and  nucleole  of  Infuso- 
ria in  coition,  we  shall  briefly  sketch  the  course  of 
psychical  phenomena  through  which  the  ciliated  Infu- 
soria pass  when  making  ready  for  copulation. 

We  shall  follow  in  the  footsteps  of  M.  Balbiani, 
freely  using  his  descriptions,  the  exactitude  of  which 
has  since  been  confirmed  by  Gruber. 

To  appreciate  fully  the  significance  of  the  facts  to 
be  adduced  herewith,  we  must  recall  to  mind  that 
throughout  the  entire  animal  kingdom  the  act  of  sex- 
ual coition  is  invariably  preceded  by  an  introductory 
manifestation  of  psychical  activity,  which  may  last  for 
quite  an  extended  length  of  time. 

The  female,  when  pursued  by  the  male,  seems  to 
be  animated  by  two  conflicting  desires — that  of  yield- 
ing to  the  male  and  that  of  repelling  his  approaches. 
This  show  of  unwillingness,  which  is  but  temporary 
and  more  seeming  than  real,  has  the  effect  of  inciting 
the  male  to  attempt  an  exhibition  of  powers  calculated 
to  captivate  the  female.  According  to  M.  Espinas, 
who  has  thoroughly  studied  this  subject,  there  are  five 
classes  of  phenomena  which  assist  in  preparing  the 
way  for  sexual  union:  firstly,  provocative  contact,  the 
lowest  of  all  these  phenomena — that  is,  the  one  which 
most  approximates  to  the  physiological  order;  sec- 
ondly, odor;  thirdly,  color  and  form;  fourthly,  noise 
and  sound;  fifthly,  play,  or  every  variety  of  move- 
ment. It  appears  to  us  that  almost  all  manifestations 
of  love  in  human  beings  themselves  could  be  classi- 
fied into  these  five  categories. 

Among  the  simplest  forms  of  life  we  meet  with  in- 


OF  MICR O-  ORGANISMS.  67 

cipient  traces  of  such  aesthetical  manifestations  point- 
ing towards  the  preparation  of  two  animals  for  sexual 
intercourse. 

"  It  is  curious,"  remarks  M.  Balbiani,  "  to  find 
among  these  organisms  which  all  zoologists,  by  reason 
of  their  diminutive  size  and  extreme  simplicity  of 
structure,  have  placed  at  the  remotest  limit  of  the  animal 
kingdom,  acts  that  mark  the  existence  of  phenomena 
analogous  to  those  by  which  the  sexual  instinct  is  ex- 
hibited in  a  large  number  of  Metazoans.  Upon  the 
approach  of  the  period  for  propagation,  the  Paramecia 
come  in  from  all  points  of  the  fluid  and  assemble  like 
little  whitish  clouds  in  more  or  less  numerous  groups 
about  the  objects  that  float  upon  the  surface  of  the 
water,  or  adhere  to  the  side  of  the  vessel  containing 
the  tiny  artificial  sea  in  which  the  animalcula  are  held 
captive.  Intense  excitement,  which  the  need  of  food 
does  not  suffice  to  explain,  prevails  in  each  of  these 
groups;  a  higher  instinct  appears  to  dominate  all  these 
tiny  organisms;  they  seek  each  other's  company,  chase 
each  other  about,  feel  here  and  there  with  their  cilia, 
adhere  for  a  moment  or  so  in  an  attitude  of  sexual  co- 
ition, and  then  retire,  soon  to  begin  anew.  When 
these  minute  assemblages  are  dispersed  by  shaking 
the  liquid,  they  quickly  form  again  at  other  points. 
These  singular  antics  wherewith  animalcula  appear 
to  incite  each  other  mutually  to  copulation  often 
continue  for  several  days  before  the  latter  act  is  defin- 
itely effected. 

"  Other  Infusoria,  particularly  the  Spirostomes,  seek 
the  deep  spots  of  the  liquid,  or  bury  themselves  in  the 
oozy  sediment  of  the  bottom,  not  to  come  forth  again 
until  they  have  separated.  The  Stentors  have  differ- 
ent habits.  They  are  affixed  by  their  pedicles  to  sub- 


68  THE  PSYCHIC  LIFE 

merged  vegetable  patches,  which  they  often  cover  like 
small,  closely-mown  lawns,  of  a  green,  brown,  or  blue 
color,  according  to  the  species;  they  turn  the  forward 
part  of  their  bodies,  which  is  elongated  in  the  shape 
of  a  trumpet,  about  in  all  directions,  and  seek  to  unite 
with  each  other  by  the  broadened  extremity  which 
corresponds  to  the  bell  of  the  trumpet." 

Among  the  numerous  species  forming  part  of  the 
group  of  Oxytrichinae,  the  act  of  coition  likewise  ex- 
hibits certain  interesting  preliminaries.  The  two 
individuals,  whose  bodies  are  generally  very  much 
flattened,  and  of  which  the  lower  sides  are  provided 
with  cilia  at  times  strongly  developed,  superpose  them- 
selves upon  each  other  on  the  ventral  side  and  mutu- 
ally entangle  the  cilia  which  cover  that  region,  while 
with  their  cornicles,  or  anterior  tentacles,  they  touch 
repeatedly  the  different  parts  of  each  other's  bodies. 
These  introductory  moves  frequently  last  for  several 
hours  before  copulation  begins. 

As  regards  the  act  of  copulation  itself,  it  too  is  of 
exceeding  interest  to  the  psychologist,  who  can  ad- 
mire the  precision  with  which  the  two  individuals  as- 
sume the  attitude  necessary  for  fecundation. 

During  conjugation  the  two  ciliated  Infusoria  are 
always  joined  together  at  the  aperture  which  forms 
the  mouth.  It  has  been  thought  that  this  aperture 
must  play  the  part  of  a  sexual  orifice  through  which  the 
two  animalcula  in  copulation  effected  the  exchange 
of  reproductive  matter;  it  has  been  suggested,  more- 
over, that  an  especial  sexual  orifice  was  present,  quite 
close  to  the  mouth;  but  these  questions  of  structure 
are  still  doubtful. 

The  attitude  of  these  organisms  during  copulation 


OF  MICR O-  OR  GANISMS.  69 

varies  according  to  the  position  of  the  mouth  which 
in  certain  groups  is  lateral  and  in  others  terminal. 

The  greater  number  of  species  have  a  lateral  mouth. 
To  this  class  belong  the  Paramecia;  these  Infusoria, 
in  which  the  buccal  fosse  lies  at  the  bottom  of  a  deep 
excavation  made  in  the  ventral  face,  cover  each  other 
over  the  whole  extent  of  this  face,  exuding  a  gluti- 
nous substance  which  causes  them  to  adhere  in  this 
position;  the  two  mouths  then  lie  exactly  upon  each 
other.  Copulation  lasts  from  twenty-four  to  thirty-six 
hours  with  the  Paramcecium  aurelia;  it  lasts  several 
days  (five  or  six)  with  the  Paramcecium  bursaria. 
Among  the  Oxytrichinae,  the  two  animals  in  conjuga- 
tion blend  together  at  an  important  part  of  their  per- 
sons in  a  very  intimate  fashion. 

We  next  arrive  to  the  second  group  of  Infusoria, 
which  show  a  terminal  mouth;  of  this  type  we  have 
had  a  specimen  in  the  Didinium  nasutum,  the  curious 
hunter  Infusory;  we  may  further  mention  the  Coleps, 
the  Nassula,  the  Prorodon.  The  two  organisms,  in 
this  case,  do  not  embrace  laterally,  they  take  a  posi- 
tion end  to  end,  connected  by  their  anterior  extremi- 
ties, mouth  opposite  to  mouth;  then,  little  by  little, 
while  still  joined  at  the  buccal  extremity,  they  shift 
about  until  they  meet  length  to  length. 

We  shall  mention  particularly,  but  briefly,  the  cu- 
rious phenomena  that  accompany  fecundation  among 
the  Vorticels.  Even  more  than  in  the  instances  just  cited 
do  these  phenomena  resemble  the  process  of  fecun- 
dation in  higher  animals,  for  in  this  instance  fecunda- 
tion is  effected  between  two  differentiated  individuals, 
one  of  which  acts  as  a  male  element  and  the  other  as 
a  female  element.  The  Vorticels  are  colonies  of  In- 
fusoria in  which  are  found  sedentary  individuals, 


70  THE  PSYCHIC  LIFE 

having  the  shape  of  minute  jugs,  and  also  detached 
individuals  called  Microgonidia,  which  are  formed  by 
repeated  divisions  upon  the  colonial  tree. 

These  Microgonidia  have  exactly  the  same  mode 
of  locomotion  as  the  spermatozoids.  Engelmann  *  has 
followed  their  movements.  He  has  seen  them  swim- 
ming about  turning  upon  their  axis  for  five  or  six 
minutes;  then,  having  come  into  the  vicinity  of  a  Vor- 
ticel,  they  abruptly  change  their  manner  of  movement, 
capering  about  the  latter  like  a  butterfly  flitting  about 
a  flower,  touching  it,  retreating,  and  then  approaching 
it  again  and  apparently  feeling  of  it;  at  last,  after 
having  visited  the  others  near  by,  they  return  to  the 
first  one  and  fasten  themselves  upon  its  surface.  The 
coition  is  not  effected  without  a  certain  show  of  re- 
sistance on  the  part  of  the  Vorticel.  It  hastily  con- 
tracts the  peduncle  to  which  it  is  attached,  at  every 
touch  of  the  Microgonidium,  while  the  latter  in  order 
to  prevent  itself  from  being  thrown  back  by  these 
rapid  shocks  and  in  order  to  be  always  close  to  the 
individual  with  which  it  wishes  to  unite,  fastens  itself 
by  an  extremely  fine  filament  to  the  style  of  the  Vor- 
ticel; thus  attached  and  drawn  along  with  the  move- 
ments of  the  latter,  it  finally  succeeds  in  effecting  a 
junction  with  it  and  in  penetrating  into  its  body.f 

It  is  now  time  to  describe  the  material  phenomena 
that  take  place  in  the  interior  of  the  two  Infusoria,  and 
which  constitute  the  material  act  of  fecundation.  The 
psychical  manifestations  which  we  have  just  noted 
and  which  so  strikingly  resemble  the  manifestations 
accompanying  the  copulative  act  in  higher  animals, 
are  of  themselves  sufficient  evidence  that  this  conju- 
gation is  a  sexual  union. 

•  Arch.  <U  ZoOloq.  txptrimtntalt.  Vol.  V,  1876. 
t  Journal  de  Micrograpkit,  1882,  p.  241. 


OF  MICR  O-  OR  GANISMS.  7 1 

The  material  changes  effected  inside  the  bodies  of 
Infusoria  in  copulation  do  not  extend  to  all  their  or- 
gans; the  main  mass  of  the  body,  the  protoplasm,  plays 
but  a  secondary  role  in  the  matter;  the  change  appears 
to  be  effected  exclusively  in  the  nucleus  and  the  nu- 
cleole. 

Let  us  further  state  that,  so  far  as  is  known,  these 
changes  are  never  effected  apart  from  coition  and  be- 
fore the  Infusoria  actually  embrace;  copulation  sets 
in  every  time,  apparently,  that  these  animals,  under 
particularly  favorable  conditions,  have  actively  repro- 
duced by  fission.  Fissiparity  is  then  seen  to  cease 
and  conjugation  appears. 

We  have  not  the  time  to  sketch  the  history  of  this 
important  question  of  physiology,  interesting  as  it  may 
be.  It  will  be  enough  to  recapitulate  what  we  actu- 
ally know  upon  the  subject,  taking  as  our  guide  sub- 
stantially the  views  of  M.  Balbiani  who,  as  is  known, 
was  the  first  scientist  to  study  the  physical  phenome- 
na connected  with  fecundation  among  Infusoria.  The 
divergencies  between  his  observations  and  those  of  an- 
other eminent  investigator,  M.  Butschli,  extend  in  re- 
ality only  to  points  of  detail. 

Let  us  first  mark  the  modifications  that  take  place 
within  the  Chilodon  cucullus  during  conjugation.  Each 
of  the  two  Infusoria  in  copulation  possesses  a  nucleus 
(endoplast,  main  nucleus)  and,  close  beside  this  nu- 
cleus, an  organ  considerably  smaller,  a  nucleole,  or 
attendant  nucleus,  or  latent  nucleus  (endoplastule, 
accessory  nucleus);  this  minute  body  must  not  be  mis- 
taken for  the  nucleole  that  is  often  found  in  the  inte- 
rior of  the  nucleus  among  many  Micro-organisms  and 
in  cellules;  it  has  a  function  entirely  different. 

Of  these  two  elements,  the  nucleus  plays  an  al- 


72  THE  PSYCHIC  LIFE 

most  negative  part  in  the  act  of  fecundation.  It  as- 
sumes irregular  outlines  and  becomes  rumpled,  while 
its  contents  collect  in  detached  masses  of  various  sizes: 
it  grows  clear  by  degrees  and  is  finally  absorbed.  It 
disappears,  accordingly,  by  a  phenomenon  of  regres- 
sion and  without  dividing. 

Fecundation  aims  to  replace  this  wasted  element 
by  a  nucleus  of  fresh  formation.  The  latter  is  pro- 
duced at  the  cost  of  the  little  body  we  have  described 
by  the  name  of  attendant  nucleus  or  latent  nucleus. 
The  attendant  nucleus  does  not  act  in  making  up  a 
main  nucleus  in  the  cellule  of  which  it  is  a  part;  it 
finds  its  way  into  the  body  of  the  other  animal  and  it 
is  in  this  new  cellule  that  it  is  destined  to  perform  the 
function  of  a  nucleus. 

In  the  Chilodon  cucullulus,  the  attendant  nucleus 
divides  into  two  striated  capsules,  never  more.  These 
two  capsules  grow  to  unequal  sizes;  the  largest  attains 
a  size  of  forty  thousandths  of  a  millimetre;  it  is  this 
one  that  forms  the  new  nucleus  of  the  Chilodon.  The 
second  capsule  shrinks  and  becomes  compressed;  it 
takes  its  place  beside  the  first  one  and  constitutes  the 
new  attendant  nucleus. 

To  the  study  of  this  type  of  fecundation  we  may 
limit  our  attention;  it  is  the  simplest  of  all,  and  other 
forms  may  be  comprehended  within  it  without  much 
difficulty.  What  complicates  the  process  in  the  other 
species  is  principally  the  successive  modifications 
through  which  the  old  nucleus  passes  before  suffering 
absorption.  In  the  Stentor  cceruleusthe  nucleus  has 
the  shape  of  a  long  chaplet  or  string  of  beads;  at  the 
moment  of  fecundation  the  beads  of  the  chaplet  break 
apart  and  spread  in  the  protoplasm  where  they  finally 
become  absorbed.  Among  the  Paramaecia  the  phe- 


OF  MICR  O-  OR  CAN  ISMS.  7  3 

nomenon  is  still  different:  the  nucleus,  at  first  massed 
together  in  a  cluster,  lengthens  out  into  a  very  long 
string,  which  breaks;  and  the  pieces  becoming  scat- 
tered about  in  the  protoplasm,  are  absorbed. 

We  find  that  fecundation  in  every  instance  intro- 
duces the  dispersion  and  disappearance  of  the  old  nu- 
cleus and  that  the  latter  is  replaced  by  a  new  nucleus 
resulting  from  the  transformation  of  the  attendant  nu- 
cleus that  proceeded  from  the  other  organism. 

The  various  modifications  presented  by  this  atten- 
dant nucleus  likewise  contribute  in  great  measure  to 
the  complexity  of  the  phenomenon.  We  have  seen 
that  in  the  Chilodon  the  attendant  nucleus  breaks  into 
two  globules,  of  which  one  goes  to  form  the  new  nu- 
cleus and  the  other  the  new  attendant  nucleus.  Mat- 
ters take  a  different  course  in  the  Paramaecia.  In  the 
Paramcecium  bursaria,  for  instance,  the  attendant  nu- 
cleus divides  into  two  and  then  into  four  capsules; 
one  of  these  capsules  suffers  absorption,  a  second  one 
becomes  the  attendant  nucleus,  and  the  two  others 
coalesce  with  what  remains  of  the  old  nucleus  to  form 
the  nucleus  proper.  In  the  Paramcscium  aurelia  the  di- 
vision is  made  into  eight  capsules;  three  are  cast  out, 
and  of  the  five  left  four  are  meant  to  form  the  new 
main  nucleus;  in  reality,  each  Paramaecium  segmen- 
tates  first  into  two  and  then  into  four  divisions,  and 
each  of  these  four  individuals  takes  one  of  the  capsules. 
The  fifth  capsule  is  designed  to  form  the  attendant 
nucleuses  of  these  four  organisms;  it  divides,  accord- 
ingly, into  two  and  then  into  four  parts;  that  is  to  say, 
into  as  many  parts  as  the  body  of  the  animal  divided. 

There  is  no  question  in  our  mind  but  that  conjuga- 
tion in  this  case  is  a  sexual  phenomenon.  A  circum- 
stance that  at  the  outset  confirms  this  is  the  peculiar 


74  THE  PSYCHIC  LIFE 

manoeuvering  the  animalcula  go  through  before  aban- 
doning themselves  to  copulation;  the  movements  they 
execute  admit  of  exact  comparison  with  the  actions 
attendant  upon  copulation  among  higher  animals.  But 
we  shall  recur  further  on  to  the  physiological  signifi- 
cance of  conjugation,  when  we  shall  endeavor  to  ex- 
plain, according  to  the  most  recent  investigations,  the 
function  of  the  nucleus  in  the  cellule. 

The  question  may  be  asked,  what  is  the  starting- 
point,  the  provocative  of  these  sexual  phenomena,  the 
cause  that  sets  them  in  play.  Biitschli  justly  thinks, 
that  conjugation  is  determined  by  internal  causes;  in 
fact,  it  takes  place  directly  after  very  active  periods  of 
spontaneous  division,  as  Balbiani  has  shown.  When 
we  bear  in  mind  that  the  object  of  conjugation  is  to 
replace  the  old  nucleus  which  has  become  wasted  and 
worn  out,  we  may  conjecture  with  some  degree  of  like- 
lihood that  the  physiological  condition  of  the  nucleus 
constitutes  the  sexual  excitant  that  causes  the  Infuso- 
ria to  copulate. 

However  that  may  be,  a  curious  observation  witn 
the  Paramacium  aurelia  has  made  us  acquainted  with 
one  of  the  structural  conditions  of  the  sexual  instinct 
in  that  Infusory.  For  a  long  time  J.  Muller  had  pointed 
to  the  presence  of  filaments  in  the  nucleus  and  even 
nucleolus  of  Paramaecia,  that  had  the  appearance  of 
spermatozoids.  Observations  to  the  same  effect  have 
increased  since  then,  and  it  is  now  known  that  the 
filaments  are  Schizomycetes,  parasitic  Bacilli,  which 
find  their  way  into  the  nucleus  and  nucleolus,  and  mul- 
tiply, after  their  customary  mode  of  segmentation,  by 
disarticulation.  Balbiani  has  definitely  determined 
the  nature  of  these  filaments  by  morphological  and 
micro-chemical  methods;  he  has  found  out,  among 


OF  MICR  O-  OR GANISMS.  75 

other  things,  that  the  filaments  do  not  dissolve  in 
strongly  concentrated  alkaline  solutions;  and  it  is 
known  that  Bacteria  exhibit  this  peculiar  attribute  of 
offering  a  great  resistance  to  destructive  agents. 

In  the  nucleus  which  they  have  penetrated,  these 
parasites  induce  a  pathological  condition  that  results 
in  destroying  every  manifestation  of  the  sexual  in- 
stinct in  this  Infusory.  Among  a  swarm  of  animals  of 
this  species  that  are  in  copulation,  single  individuals 
are  found  that  show  a  nucleus  and  nucleolus  corn- 
completely  charged  with  Bacteria;  sometimes  these 
organs  suffer  an  enormous  dilatation,  the  nucleus  be- 
coming nothing  more  than  an  enveloping  membrane 
which  is  filled  like  a  huge  pouch  with  parasites.  The 
animal  continues  to  live,  but  it  no  longer  attempts  to 
copulate. 

VII. 

It  is  not  our  intention  to  make  a  full  and  complete 
study  of  fecundation  in  higher  animals  and  plants; 
there  is  but  one  phase  of  that  phenomenon  that  can 
enter  into  a  general  study  of  Micro-organisms,  and  that 
is  the  history  of  the  sexual  elements,  of  their  form, 
their  movements,  and  lastly  their  copulation. 

We  shall  describe  animal  fecundation  first,  and 
plant  fecundation  afterwards;  regarding  these  phe- 
nomena particularly  from  a  psychological  standpoint. 

Among  metazoans,  fecundation  may  be  divided 
into  two  distinct  acts.  The  first,  and  most  apparent, 
consists  of  the  union  of  the  two  individuals;  of  this  we 
shall  not  have  to  speak  here;  it  is  a  phenomenon  that 
lies  outside  the  limits  of  our  investigations.  The  sec- 
ond, more  deep-seated,  consists  in  the  phenomena 


76  THE  PSYCHIC  LIFE 

that  take  place,  after  copulation,  between  the  sperma- 
tozoid  and  the  ovule. 

There  are  numerous  reasons  for  comprehending  a 
study  of  the  generative  elements  within  a  general  in- 
vestigation into  the  nature  of  Micro-organisms. 

In  the  very  first  place,  it  must  be  taken  into  ac- 
count, that  these  two  elements  are  represented  in  ani- 
mals by  a  single  cell. 

The  ovule  appears  as  a  minute  microscopic  sphere 
enclosed  by  an  envelope  (vitelline  membrane);  it  is 
formed  of  a  mass  of  granulous  protoplasm  (vitellus) 
containing  a  nucleus  (germinative  vesicle)  and  one  or 
many  nucleoli  (germinative  spot).  The  spermatozoids, 
in  vertebrates,  have  quite  a  different  aspect:  they  are 
filaments  of  varying  lengths,  having  a  distended  part, 
or  head,  and  a  tapering,  attenuated  part,  or  tail. 

The  resemblance  that  spermatozoids  bear  to  Pro- 
tista, at  first  caused  them  to  be  regarded  as  animals 
living  a  parasitic  life  in  the  spermatic  fluid.  Ehren- 
berg  classed  them  among  the  polygastric  Infusoria. 
Kcelliker  and  Lallemand  were  the  first  to  reject  this 
notion  and  the  first  to  regard  spermatozoids  as  ele- 
mental parts  of  living  tissues,  having  the  morpho- 
logical value  of  a  cellule.  They  are  now  likened  to  de- 
tached cellular  elements,  such  as  blood-globules. 

Whatever  form  they  assume,  the  sexual  elements 
live  as  minute  organisms  independent  of  the  individ- 
ual from  which  they  originated.  This  circumstance  is 
particularly  remarkable  in  the  case  of  the  male  element, 
the  spermatozoid,  which  retains  its  vitality  for  a  cer- 
tain space  of  time  after  its  expulsion.  The  length  of 
this  period  varies  with  the  different  species.  Whereas 
the  spermatozoids  thrown  from  a  trout  lose  all  motion 
in  the  water  after  the  expiration  of  a  few  seconds, 


OF  MICR  O-  OR GANISMS.  77 

those  of  the  bee,  in  the  seminal  reservoir  of  the  fe- 
male, remain  alive  for  several  years.  The  seminal  ele- 
ments of  mammifers  live  for  quite  some  time  in  the 
genital  passages  of  the  female.  Balbiani  has  found 
living  spermatozoids  in  the  ducts  of  a  she-rabbit  twenty 
hours  after  coition.  Ed.  van  Beneden,  Benecke,  Eimer, 
Fries,  have  observed  that  the  sperm  retains  its  prop- 
erties in  the  uterus  of  bats  for  several  months. 

Another  remarkable  circumstance  is,  that  the  cop- 
ulation of  the  two  sexual  elements  is  not  without  anal- 
ogy to  the  copulation  of  the  two  animals  from  which 
they  originated.  The  spermatozoid  and  the  ovule,  to 
some  extent,  repeat  on  a  small  scale  what  the  two  in- 
dividuals perform  in  their  larger  sphere.  Thus,  it  is 
the  spermatozoid  that,  in  its  capacity  of  male  element, 
goes  in  quest  of  the  female.  It  possesses,  in  view  of 
the  journeys  it  has  to  make,  organs  of  locomotion  that 
are  lacking  in  the  female  and  are  useless  to  it.  The 
spermatozoid  of  man  and  of  a  great  number  of  mam- 
mifers is  equipped  with  a  long  tail,  the  end  of  which 
describes  a  circular  conical  movement,  which  together 
with  its  rotation  about  its  axis,  determines  the  forward 
motion  of  the  spermatozoid.  The  same  mode  of  pro- 
gression is  seen  in  the  zoospores  of  Algae  and  in  Masti- 
gophores,  which  are  armed  with  flagella;  the  move- 
ments of  the  spermatozoid  have  been  not  improperly 
compared  to  those  of  a  Flagellate. 

Other  spermatozoids  like  those  of  the  Triton  and 
Axolotl  are  provided  with  a  different  kind  of  locomo 
tive  apparatus;  it  consists  of  an  undulatory  membrane 
that  acts  like  a  real  fin;   the  spermatozoid  moves  for- 
ward without  turning  about  on  its  axis. 

There  has  been  much  discussion  as  to  the  nature 
of  the  forces  that  account  for  the  movements  of  the 


78  THE  PSYCHIC  LIFE 

fecundative  elements.  The  early  investigators  that 
concerned  themselves  with  the  study  of  animalcula, 
naturally  attributed  to  them  spontaneous  and  volun- 
tary movement.  Since  the  spermatozoid  has  been  re- 
garded as  nothing  else  than  an  histological  element, 
endosmotic,  hygroscopic  and  like  actions  have  been 
accepted  in  explanation.  M.  Balbiani,  from  whom  we 
have  taken  the  foregoing  details,  declares  that  expla- 
nations of  this  character  are  none  at  all;  for,  upon  ul- 
timate analysis,  all  kinds  of  motion  may  be  reduced 
to  a  chemical  or  physical  action — sarcodic  or  ciliary 
movement  just  as  much  as  voluntary  movement.  "  For 
my  part,"  our  scientist  adds,  "  I  believe  that  the  sper- 
matozoids  do  not  move  about  blindly  but  that  they 
act  in  obedience  to  a  kind  of  internal  impulsion,  to  a 
sort  of  volition  which  directs  them  towards  a  definite 
object."*  The  experiments  of  M.  Balbiani  have  shown 
that  with  weak  solutions  of  ether  and  chloroform  the 
movements  of  the  spermatozoids  may  be  moderated 
and  made  to  cease  so  slowly  that  the  latter  are  yet  able 
to  fecundate  the  ovules. 

In  fine,  the  spermatic  element,  in  directing  itself 
toward  the  ovule  to  be  fecundated,  is  animated  by  the 
same  sexual  instinct  that  directs  the  parent  organism 
towards  its  female. 

In  the  higher  animals,  the  movements  of  the 
spermatozoid  that  is  endeavoring  to  reach  the  fe- 
male exhibit  a  peculiar  character,  which  it  is  im- 
portant to  emphasize:  these  movements  do  not  ap- 
pear to  be  directly  provoked  by  an  exterior  object,  as 
those  of  micro-organisms  are;  the  spermatozoid  en- 
deavors to  reach  an  ovule  which  is  frequently  situated 
a  great  distance  away;  this  is  the  case  particularly 

•  La  G4a£ratioo  des  Vertibrls,  p.  159. 


OF  MICR  O-  OR  GANISMS.  79 

with  animals  that  fecundate  internally,  with  birds  and 
mammifers.  The  place  of  fecundation  is  still  imper- 
fectly known.  Coste  at  one  time  accepted  the  theory 
that  the  spermatozoid  and  ovule  met  in  the  ovary. 
Fecundation  probably  takes  place  in  the  fore  part  of 
the  oviduct.  It  has  little  to  do  with  our  purpose,  how- 
ever, to  solve  this  delicate  question  precisely.  A  fact 
that  is  important  to  mention  in  a  general  way  is  the 
length  of  road  the  spermatozoid  has  to  traverse  before 
coming  up  with  the  ovule. 

Let  us  now  follow  the  spermatozoid  in  its  journey 
to  the  ovule.  It  is  known  that  the  road  it  has  to  tra- 
verse is,  in  certain  instances,  extremely  long.  Thus, 
in  the  hen  the  oviduct  measures  60  centimeters,  and 
in  large  mammifers  the  passages  have  a  length  of 
from  25  to  30  centimeters.  We  might  ask  ourselves 
how  such  frail  and  minute  creatures  come  by  a  power 
of  locomotion  great  enough  to  enable  them  to  traverse 
so  long  a  path.  But  observation  discloses  the  fact 
that  they  are  able  to  overcome  obstacles  quite  out  of 
proportion  to  their  size.  Henle  has  seen  spermato- 
zoids  carry  along  with  them  masses  of  crystals  ten 
times  larger  than  themselves,  without  appreciably  les- 
sening their  speed.  F.  A.  Pouchet  has  seen  them 
carry  bunches  of  from  eight  to  ten  blood-globules.  M. 
Balbiani  has  attested  the  same  fact.  These  globules, 
which  have  fastened  themselves  about  the  head  of  the 
spermatozoid,  have  each  a  volume  double  that  of  the 
head.  Now,  according  to  Welcker,  the  weight  of  a 
globule  of  human  blood  is  0.00008  of  a  milligramme: 
allowing  that  the  spermatozoid  has  the  same  weight, 
we  may  then  say  that  it  is  able  to  carry  burdens  four 
or  five  times  heavier  than  itself. 

The  length  of  road  traversed  is  not  the  only  remark- 


8o  THE  PSYCHIC  LIFE 

able  circumstance  here;  there  are  also  involutions  and 
intricacies  in  the  path  to  be  followed  in  reaching  the 
ovule.  In  this  connection  an  interesting  observation 
has  been  made  upon  the  silk-worm.  "  At  the  moment 
of  conjugation  the  male  deposits  its  seminal  fluid  in  a 
special  sac,  the  copulatory  sac.  The  day  following, 
this  sac,  which  was  distended  by  the  sperm,  is  com- 
pletely flaccid,  and  nearly  all  the  spermatozoids  have 
traveled  out  into  another  sac,  which  opens  into  the 
oviduct  opposite  the  first  one,  and  there  they  wait  to 
fecundate  the  ovules  as  they  pass  by.  Now,  the  walls 
of  the  copulatory  sac  have  no  contractile  power,  and 
the  passage  of  the  spermatozoids  from  one  sac  into 
the  other  can  be  attributed  only  to  a  spontaneous 
movement.  Further,  a  fact  that  well  seems  to  verify 
this,  is,  that  there  still  remains  in  the  copulatory  sac 
a  few  misformed  seminal  elements,  deprived  of  the 
power  of  locomotion."  * 

Let  us  now  note  what  happens  at  the  moment 
when  spermatozoid  and  ovule  come  in  contact  with 
one  another.  The  successive  phenomena  then  taking 
place  have  been  carefully  studied  by  Fol  in  his  work 
upon  the  star-fish  (Asterias  glacialis}.  T.he  ovule  has 
no  enveloping  membrane;  it  it  is  covered  about  only 
by  a  mucous  layer,  soft  and  flaky.  The  spermatozoids 
come  up  in  great  numbers  and  push  forward  into  this 
layer;  at  this  point  they  are  all  brought  to  a  halt  and 
become  entangled  among  each  other  with  the  excep- 
tion of  one,  which,  more  speedy  in  its  movements,  out- 
strips the  others  and  arrives  within  a  short  distance  of 
the  surface  of  the  vitellus  (or  protoplasm  of  the  ovule). 
At  that  moment,  and  before  any  contact  whatever,  there 
results  a  curious  phenomenon  of  attraction  between  the 

*  Balbiani,  Compte*  Rendus  dt  tAcad.  ties  Science*,  1869. 


OF  MICRO-ORGANISMS.  81 

ovule  and  the  spermatozoid;  the  peripheral  substance 
of  the  ovule  is  seen  to  lift  itself  up  in  front  of  the  sper- 
matazoid  in  the  shape  of  a  minute  protuberance;  this 
protuberance,  at  first,  has  a  rounded  shape,  then  it 
grows  thinner  and  forms  a  point  which  advances  to- 
wards the  spermatozoid;  this  point  is  called  the  cone 
of  attraction  (see  Fig.  8).    The  head  of 
the  spermatozoid  fastens  itself  upon  the 
cone,  which  seems  to  draw  it  into  its  in- 
terior. The  tail  of  the  spermatozoid  does 
not  appear  to  enter  into  the  interior  of 
the  ovule  and  take  part  in  the  process  of 
•  •.:.*:.;-       fecundation,  which  consists  simply  in  the 
Fis.  <?.— A  small  fusion  of  the  head  of  the  spermatozoid 

portion  of  the  ovule        . 

of  a  star-fish  (Aste-  with  the  nucleus  of  the  cellule. 

riasglacialis) 

showing  the  forma-         As  soon  as  the  head  of  the  spermato- 

tion  of  the  cone  of 

attraction.    (AC-  zoid  has  penetrated  into  the  ovule,  the 

cording  to  Fol.)  . 

latter  enwraps  itself  in  an  envelope,  to 
protect  itself  against  the  other  male  elements.  It  ap- 
pears, in  fact,  to  be  well  settled  that  the  penetration 
into  the  vitellus  of  several  spermatozoids  marks  the 
beginning  of  an  adverse  change:  the  subsequent  seg- 
mentation of  the  ovule  is  irregular,  and  development 
ceases. 

The  membrane  in  which  the  fecundated  ovule  of 
the  Asterias  glacialis  infolds  itself,  is  formed  by  a  con- 
densation of  the  peripheral  layer  of  the  vitellus;  the 
condensation  starts  from  about  the  point  where  the 
spermatozoid  penetrated,  and  gradually  spreads  over 
the  whole  surface  of  the  ovule;  the  formation  of  this 
protective  membrane  is  so  rapidly  effected,  that  access 
to  the  ovule  is  barred  against  spermatozoids  who  might 
be  only  a  few  seconds  behind  the  first  one. 

Sexual  selection,  then,  acts  among  spermatozoids 


8a  THE  PSYCHIC  LIFE 

just  as  among  all  animals;  it  is  the  most  agile  and 
the  stoutest  spermatozoid  that  first  penetrates  the  ovule 
and  effects  fecundation.  The  laws  of  selection,  thor- 
oughly developed  by  Darwin,  do  not  only  apply  to  in- 
dividuals; they  apply  also  to  sexual  elements. 

We  are  unable  to  follow  the  successive  modifica- 
tions suffered  by  the  head  of  the  spermatozoid  after 
its  entrance  into  the  ovule;  we  may  state  simply,  that 
the  head  presents  the  appearance  of  a  radiate  figure, 
of  a  diminutive  sun  advancing  towards  the  female  nu- 
cleus. At  the  same  moment,  the  female  nucleus  ap- 
pears affected  and  puts  itself  in  motion  towards  the 
spermatic  nucleus.  The  two  nuclei  soon  come  almost 
within  contact,  and  it  is  in  particular  the  female  nu- 
cleus that  then  plays  the  active  part.  It  is  disturbed 
by  incessant  movements  and  every  moment  changes 
its  form;  it  thrusts  out  prolongations  towards  the  male 
nucleus,  and  one  of  these  prolongations  fastens  itself 
upon  the  latter,  presenting  at  the  end  a  minute  de- 
pression in  the  shape  of  a  cup,  which  receives  the  male 
nucleus;  and  the  two  nuclei,  while  executing  active 
movements,  fuse  into  one  another.  In  this  manner 
the  first  nucleus  of  segmentation  is  created. 

Selenka  has  furnished  interesting  chronological 
data  as  to  the  time  of  appearance  of  the  different  phe- 
nomena. The  time  is  in  each  case  taken  from  the  mo- 
ment of  artificial  fecundation.  After  a  lapse  of  five 
minutes,  the  spermatozoid  has  forced  an  entrance  into 
the  ovule.*  At  the  expiration  of  ten  minutes  (that  is, 
five  minutes  after  entrance),  it  has  reached  the  centre 
of  the  ovule.  At  twelve  minutes,  the  female  nucleus 
has  put  itself  in  motion  to  meet  the  spermatic  nucle- 


*  M.  Balbiani,  Court  tur  laficondation,  passim.   Journal  de  Micrograpkit 
Vol.  III.  1879. 


OF  MICR  O-  OR  G AN  I  SMS.  83 

us.  Finally,  at  the  twentieth  minute,  the  two  nuclei 
have  united. 

In  the  psychical  history  of  animal  fecundation  as 
just  given,  there  are  many  gaps:  the  history  of  vege- 
table fecundation  will  fill  several  of  these. 

The  simplest  forms  of  sexual  reproduction  in  veg- 
etables are  those  where  the  male  and  female  cellules 
are  quite  the  same  and  advance  to  meet  each  other 
equally;  thus  possessing  not  only  the  same  form,  but 
also  the  same  properties.  In  a  small  Alga  bearing  the 
name  of  Ulothrix  serrata,  the  interior  of  certain  cellules 
divides  into  two  parts,  which  separate,  then  come  to- 
gether again  and  mingle  anew  into  a  minute  mass 
which,  when  set  at  liberty,  reproduces  the  plant  entire. 
In  other  species  the  inside  divides  into  small  naked 
cellules,  which  are  first  set  at  liberty  and  for  some 
time  move  briskly  about  in  the  water  by  means  of  cilia 
with  which  they  are  provided,  before  fusing  into  one 
another.  These  cellules  are  called  zoospores.  The 
differentiation  is  further  marked  in  certain  species,  the 
zoospores  of  which  have  neither  the  same  form  nor  the 
same  properties.  Some  leave  their  positions  to  go  to 
meet  the  others:  these  are  the  male  cellules,  the  an- 
therozoids;  others  make  no  movement  at  all  and  limit 
their  role  to  that  of  waiting:  these  are  the  zoospores. 
Similarly,  in  an  Alga  bearing  the  name  of  Spharoplea 
annulina,  there  are  found  two  kinds  of  filaments, 
brown  and  green.  In  the  green  filaments  the  proto- 
plasm of  certain  cellules  breaks  up  into  a  definite  num- 
ber of  ovoid  bodies  which  remain  immobile;  in  the  in- 
terim, the  cellules  of  the  brown  filaments  liberate  mo- 
bile spores  provided  with  two  flagella:  these  spores, 
veritable  male  cellules,  ply  briskly  about  in  the  water 
and  then  proceed  to  fix  themselves  to  the  green  fila- 


84  THE  PSYCHIC  LIFE 

ments,  the  cellules  of  which  are  pierced  by  pores; 
through  these  orifices  they  penetrate  into  the  cellules 
and  fuse  with  the  immobile  ovoid  bodies,  which  are 
nothing  else  than  zoospores. 

The  psychkal  phenomena  attending  this  mode  of 
conjugation  may  be  still  more  complicated,  as  shown 
by  the  observation  that  Berthold  has  made  upon  the 
conjugation  of  the  zoospores  of  the  Ectocarpus  silicu- 
losus.  The  Ectocarpus  belongs  to  a  group  of  algae  char- 
acterized by  the  presence  of  mobile  spores  which  re- 
produce the  plant.  These  zoospores  are  little  pear- 
shaped  cellules,  of  which  the  tapering  end  is  colorless, 
and  the  rounded  end  shows  a  brownish-green  colora- 
tion, which  is  due  to  the  presence  of  an  extensive 
chromatophore;  at  the  edge  of  the  chromatophore  a 
deep  depression  is  sharply  marked,  which  appears  to 
be  an  eye.  Every  zoospore  is  equipped,  in  addition, 
with  two  flagella,  which  rise  from  the  same  point  of 
the  lateral  skirt  of  the  anterior  extremity  of  the  body; 
one  of  these  flagella  points  forwards  and  the  other 
backwards.  When  the  zoospores  are 
set  at  liberty  and  begin  to  swim  about 
in  the  water,  they  pass  each  other  by 
unnoticed.  The  female  cellule  does 
not  draw  about  her  the  male  cellules, 
from  which,  moreover,  it  differs  by  no 
Fig.  9. —Sexual  re-  morphological  mark.  But  at  a  given 

production  of  the  Ecto- 

carput  tiiicuiostu.  oif-  moment  the  female  zoospore  becomes 

ferent  stages  of  the  fe- 
male  zoospore  while  distinguished   from  the  male  cellules 

entering    the    state    of  . 

rest  (after  Berthold).  by  passing  into  a  state  of  rest;  where- 
to, the  base  of  the  anterior  flagellum,  which  is  laterally 
inserted,  proceeds  to  blend  with  the  anterior  part  of 
the  body  with  the  effect  that  the  flagellum  appears  to 
rise  from  the  extremity;  during  the  same  time,  it 


OF  MICR  O-  OR GANISMS.  85 

contracts,  and  presents  at  its  free  end  a  slight  pro- 
tuberance, which  allows  the  zoospore  to  fix  itself  upon 
an  immobile  point;  as  to  the  rear  flagellum,  it  slips 
back  upon  the  posterior  part  of  the  body  which  it 
encompasses,  and  finally  disappears. — When  the  fe- 
male zoospore  has  become  motionless,  the  male  zoo- 
spores,  hitherto  indifferent,  are  seen  to  make  towards 
it  and  to  surround  it  in  a  half-circle;  the  number  of 
zoospores  that  thus  meet,  is  quite  considerable;  it 
frequently  exceeds  a  hundred 
(fig.  10).  They  let  their  second 
flagellum  float  loosely  behind 
them,  while  they  all  direct  their 
anterior  filament  towards  the  fe- 
male cellule;  this  filament  they 
draw  back  and  forth  over  the 
Fig.  10.  —  sexual  reproduc-  body  of  the  female  cellule;  they 

tion   of   the   Ectocarpus  silicu-  r  •.  i  r  r       1 

iosus.      Female    zoospore    sur-    perform  Upon  it  real  acts  Of  feel- 
rounded  by  male  zoospores.          •  ,  i  r  •  r         i   •    i     • 

ing,  the  object  of  which  is  evi- 
dently to  provoke  in  the  female  zoospore  a  genital  ex- 
citation, as  what  follows  will  prove.  It  happens  at 
times  that  several  of  the  male  zoospores  quit  the 
ranks  and  make  off;  they  are  immediately  replaced  by 

others  who    employ 
their  filaments  in  a 
^_        like  manner,  to  stroke 
^j^j)     the  female.    Finally, 
upon  the  expiration 
of  a  certain  time, 

Fig.  n.  —  Sexual  reproduction  of  the  Ecto-  One  of  the  ZOOSpOrCS 

carpus  siliculosus.     Successive    stages    of  the  i  ,1          i      ir 

copulation  of  a  female  zoospore  with  one  of  the  leaves  tile     nall-Cir- 

male  zoospores.  ,  j                           i 

cle   and   approaches 

the  female.     The  two  zoospores  unite;  after  having 
presented  the  series  of  changes  marked  in  the  figure, — 


86  THE  PSYCHIC  LIFE 

when  the  fusion  is  complete, — the  female  cellule  loses 
its  fixatory  filament  and  the  little  zygote,  the  result  of 
the  fusion,  is  set  free. 

When  the  male  zoospore  is  obliged  to  go  a  long 
distance  to  reach  the  female  zoospore,  it  has  been 
thought  that  the  latter  secretes  a  substance  which  acts 
upon  the  male  cellule  as  a  chemical  excitant  and 
which  marks  out  for  him  the  direction  to  follow.  The 
supposition  is  quite  probable;  it  was  suggested  by 
Strasburger,  who  had  shown  that  the  spermatozoids 
of  the  Marchantia  polymorpha  are  attracted  by  the 
substance  that  issues  from  the  archegonium.  It  will 
only  be  necessary  to  assist  at  an  experiment  of  artifi- 
cial fecundation  with  fish-spawn,  in  order  to  come  to 
the  same  opinion.  The  sperm  introduced  into  the 
liquid  preparation  does  not  spread  about  homogene- 
ously in  all  directions;  the  spermatozoids  are  observed 
to  whirl  about  the  ovules  in  great  masses;  it  must  be 
supposed,  further,  that  there  is  some  excitation  of  an 
unknown  nature  which  attracts  the  spermatozoid  to- 
wards the  micropyle,  for  this  minute  opening,  of  which 
the  diameter  is  scarcely  that  of  the  head  of  a  sperma- 
tozoid, is  the  only  orifice  through  which  the  male  ele- 
ment can  enter  into  the  ovule  to  fecundate  it. 

These  ingenious  opinions  have  been  latterly  con- 
firmed by  the  very  interesting  experiments  of  M. 
Pfeffer,  professor  at  the  University  of  Tubingen,  upon 
the  movements  of  spermatozoids.*  His  investigations 
had  to  do  principally  with  the  spermatozoids  of  cryp- 
tograms. M.  Pfeffer  discovered  that  certain  chemical 
substances  have  the  property  of  attracting  these  sper- 
matozoids. 


*  Pfeffer,    Unttrtttchungtn    ant    firm    fotaniicktn    fnititut    *u     Tubingen, 
Vol.  I.     Leipzig.  1884,  p.  363. 


OF  MICR  O-  OR  G  AN  ISMS.  87 

The  manner  of  conducting  the  experiment  is  as 
follows.  A  solution  of  the  substance  to  be  experi- 
mented upon  fs  placed  in  small  capillary  tubes  with  a 
light-aperture  of  from  five  to  seven  hundredths  of  a 
millimeter  wide.  These  capillary  tubes  dip  into  a 
watch-crystal  covered  with  a  liquid,  wherein  quantities 
of  spermatozoids  have  been  placed.  Under  these  cir- 
cumstances currents  of  diffusion  are  soon  set  up  be- 
tween the  tube  and  the  liquid  in  the  watch-crystal, 
and  when  the  substance  experimented  upon  is  the 
proper  one,  the  spermatozoids  are  seen  to  follow  the 
currents  of  diffusion  and  to  penetrate  into  the  tube. 

The  substance  exerting  such  attraction  varies 
with  the  plants.  The  author  began  by  experimenting 
upon  the  spermatozoids  of  certain  ferns  (Adiantum 
ctineatuni}.  After  a  great  many  fruitless  trials,  one 
substance,  and  one  only,  proved  to  be  effective: 
namely,  a  solution  of  malic  acid  or  malate.  It  is  to  be 
presumed,  then,  that,  in  the  organic  kingdom,  malic 
acid  must  be  the  substance  acting  as  a  chemical  ex- 
citation upon  the  spermatozoids  of  ferns  and  guiding 
them  towards  the  female  cellule. 

According  to  the  hypothesis  of  Pfeffer,  the  actual 
process  takes  place  in  the  following  manner.  The 
spore  of  a  fern,  falling  upon  humid  ground,  germinates 
and  gives  birth  to  a  green  cordate  slip,  the  prothal- 
lium,  upon  which  are  developed  the  male  organs  or 
antheridia,  and  the  female  organs  or  archegonia.  At 
a  certain  moment,  elongate  cellules,  spirally  twisted 
and  extremely  mobile,  issue  from  the  antheridium: 
these  are  the  spermatozoids.  They  are  equipped  with 
vibratile  cilia,  by  the  help  of  which  they  are  able  to 
start  in  search  of  the  female  cellule.  At  the  same  in- 
stant, the  female  organ,  the  archegonium,  opens  and 


88  THE  PSYCHIC  LIFE 

emits  a  mucilaginous  substance,  which  must  contain 
malic  acid  or  a  malate,  for  these  compounds  are  the 
particular  excitatory  substance  of  the  fern-spermato- 
zoids.  Thanks  to  a  drop  of  dew  that  falls  upon  the 
prothallium,  the  spermatozoids  swim  around  and  ap- 
proach the  female  ovule,  which  attracts  them  by  acting 
upon  them  with  the  malic  acid. 

A  confirmation  of  this  hypothesis  is  primarily  the 
fact,  that  all  substances  tested,  with  the  exception  of 
malic  acid  and  malates,  remained  completely  inactive; 
another  proof  is,  that  malic  acid  is  found  in  prothal- 
lium-decoctions  of  the  Pteris  serrulata  and  of  the  Ad- 
iantum  capillus  veneris;  another  proof  still,  is  the  cir- 
cumstance that  malic  acid  is  largely  diffused  through- 
out the  vegetable  kingdom. 

The  author  has  made,  in  this  connection,  a  series 
of  very  curious  experiments  upon  the  degree  of  con- 
centration necessary  to  attract  the  spermatozoids. 
The  lower  limit  at  which  attraction  begins,  is  found  in 
a  solution  containing  malic  acid  in  the  proportion  of 
one  to  1000  parts.  This  the  author  has  designated 
by  a  favorite  word  of  the  Germans:  Reiz-Schwelle,  or, 
in  other  words,  the  threshold  of  excitation. 

When  the  solution  in  the  watch-crystal  contains 
one  part  malic  acid  to  every  thousand  parts,  in  order  to 
make  the  spermatozoids  pass  from  the  watch-crystal 
into  the  tube,  the  solution  held  in  the  tube  must  be 
thirty  times  as  strong,  or  30  x  i-iooo  =  3-100.  If  the 
liquid  in  the  watch-crystal  contains  one  part  malic 
acid  to  every  hundred  parts,  similarly  the  solution  of 
the  tube  must  be  thirty  times  as  strong,  that  is  to  say 
three  tenths. 

The  author  justly  compares  the  result  of  these  ex- 
periments with  the  law  laid  down  by  Weber,  which  M. 


OF  MICR  O-  OR  GANISMS.  89 

Delbceuf  has  happily  formulated  as  follows:  "The 
slightest  difference  capable  of  being  felt  between  two 
excitations  of  the  same  sort  is  due  to  an  actual  differ- 
ence that  increases  proportionally  with  the  excitations 
themselves."  Thus,  in  order  to  tell  that  one  weight  is 
heavier  than  another,  it  must  be  heavier  than  the 
other  by  a  fractional  difference  which  varies  from  one 
third  to  one  fifth  according  to  the  individual,  be  the 
original  weight  what  it  may.  For  example,  to  a  weight 
of  three  grammes,  in  order  that  a  difference  may  be 
made  perceptible,  we  must  add  one  third  of  three 
grammes  or  one  gramme.  To  four  grammes  we  must 
add  one  third  of  four  grammes,  or  one  and  one  third 
grammes,  etc.* 

According  to  Pfeffer,  the  application  of  Weber's  law 
to  his  experiments  is  so  exact  that,  when  the  solution 
of  the  tube  is  only  twenty  times  stronger  than  that  of 
the  watch-crystal,  the  spermatozoids  remain  unaf- 
fected. Furthermore,  the  application  of  the  law  is  not 
disturbed  by  changes  of  temperature  varying  within 
certain  limits.  Thus,  down  to  a  temperature  of  -f  5° 
(41°  Fahr.)  the  spermatozoids  remain  sensible  to  a 
concentration  of  liquid  thirty  times  as  strong  as  that 
in  which  they  are. 

Basing  his  calculations  upon  these  experiments, 
the  author  has  succeeded  in  determining  the  probable 
quantity  of  malic  acid  that  must  be  contained  in  the 
archegonium.  This  quantity  is  probably  in  the  pro- 
portion of  three  tenths. 

The  spermatozoids  of  the  Selaginella  are  likewise 
wise  attracted  by  malic  acid  and  the  malates.  As  re- 
gards the  Marciliaceae,  the  specific  substance  has  not 
been  discovered.  The  same  failure,  also,  in  the  case 

*  Consult  Ribot,  Psychologie  allemande,  p.  161. 


90  THE  PSYCHIC  LIFE 

of  the  Hepaticae.  The  author  concludes  from  this, 
that  the  substance  operating  in  these  two  cases  can  be 
little  diffused  throughout  the  vegetable  kingdom. 

For  the  spermatozoids  of  the  Funaria  hygrometrica 
(Confervae),  the  operative  substance  is  cane-sugar. 
No  other  attracts  them.  The  spermatozoids  remain 
unaffected  even  by  substances  bearing  the  closest  anal- 
ogies with  cane-sugar.  We  will  cite,  by  way  of  ex- 
ample, fruit-sugar  or  levulose,  grape-sugar  or  glucose, 
glycogen,  manna,  milk-sugar,  etc.;  these  substances 
exert  no  attraction  upon  the  movements  of  the  sper- 
matozoids, whereas  cane-sugar  exercises  an  attraction 
so  powerful  that  the  capillary  tube  becomes  at  once 
crammed  with  them.  The  excitation  first  induces  in 
the  spermatozoid  a  movement  of  direction:  the  body 
is  brought  into  a  position  enabling  it  to  reach  the  tube 
by  movement  in  a  straight  line.  The  same  phenome- 
non has  been  observed  by  Strasburger  in  the  case  of 
Algae  zoospores;  when  these  minute  beings  are  at- 
tracted by  a  chemical  or  luminous  excitation,  the  first 
thing  that  happens  is  the  directing  of  the  body 
towards  the  attracting  source. 

A  solution  of  one  in  one  thousand. parts  is  suffi- 
ciently concentrated  to  draw  the  spermatozoids  of 
Mosses  into  the  capillary  tubes.  The  "  threshold  of 
excitation  "  for  them,  accordingly,  is  the  same  as  for 
the  spermatozoids  of  ferns.  Furthermore,  Weber's 
law  is  in  this  instance  again  verified;  only,  in  order  to 
have  the  chemical  excitation  produce  a  different  at- 
traction, it  must  be  stronger  than  the  first  in  the  pro- 
portion of  50  to  100.  In  the  experiments  upon  the 
spermatozoids  of  ferns  the  ratio  is  a  little  smaller;  be- 
ing only  30  to  100. 

The  question  presented  itself  to   the  author  as  to 


OF  MICR O-  OR GANISMS.  g i 

whether,  by  increasing  the  degree  of  concentration,  a 
point  would  not  be  reached  where  attraction  would 
change  to  repulsion;  he  has  not  made  the  experiment, 
but  he  has  noticed  that  great  numbers  of  spermato- 
zoids  still  penetrate  into  the  tube  when  contain- 
ing a  solution  in  the  proportion  of  15  to  100,  not- 
withstanding the  fact  that  they  there  meet  a  speedy 
death. 

The  general  conclusion  to  be  derived  from  these 
numerous  experiments  is,  first,  that  the  spermatozoids 
are  sensible  to  certain  chemical  excitations,  and  conse- 
quently, that  in  every  group  of  plants  there  exists  a 
special  substance  acting  the  part  of  a  specific  excitant 
towards  the  spermatozoids.  The  author  does  not  hes- 
itate to  regard  the  spermatozoids  as  a  physiological 
re-agent  of  such  substances,  allowing  feeble  traces  of 
the  same  to  be  detected  in  a  liquid  solution.  He  thus 
comes  to  form  a  spermatozoid  test,  which  is  not  with- 
out analogy  with  the  Bacteria  test,  invented  by  En- 
gelmann.  An  application  of  the  test  is  the  following: 
a  decoction  of  herbs  having  presented  the  property  of 
attracting  the  spermatozoids  of  Mosses,  the  author 
concluded  that  the  decoction  must  contain  cane- 
sugar. 

VIII. 
THE  PHYSIOLOGICAL  FUNCTION  OF  THE  NUCLEUS. 

It  would  be  of  the  highest  importance  to  know 
what  is  the  seat  of  the  phenomena  of  the  life  of  re- 
lation in  the  bodies  of  Micro-organisms.  We  have 
seen  that  Micro-organisms  are  the  equivalent  of  a 
simple  cellule,  composed,  according  to  the  classic 
plan,  of  a  protoplasm,  of  a  cellular  nucleus,  and  of  an 
enveloping  membrane. 


92  THE  PSYCHIC  LIFE 

Each  of  these  elements  plays  a  part  of  special  im- 
portance in  the  vital  phenomena  of  these  beings. 
Long  since,  scientists  have  attributed  movement, 
sensibility,  and  the  prehension  of  foods,  to  the  proto- 
plasm. This  was  the  result  of  direct  observation.  While 
observing  an  Amreba,  for  example,  the  protoplasm  is 
seen  to  undergo  modifications  of  form  and  to  throw 
out  pseudopods,  either  for  the  purpose  of  effecting  a 
change  of  position,  or  to  seize  alimentary  substances. 
The  protoplasm,  accordingly,  seems  to  be  the  sole 
agent  of  all  these  phenomena.  Likewise,  the  vibratile 
cilia  of  the  Ciliates,  which  are  at  once  organs  of  mo- 
tion, prehension,  and  touch;  the  suckers  of  the  Acin- 
etinidae,  which  are  special  organs  of  prehension,  are 
nothing  else  than  outward  expansions  of  the  proto- 
plasm proper. 

As  regards  the  enveloping  membrane,  the  same 
cannot  discharge  any  psychical  function:  firstly,  be- 
cause it  is  a  product  of  protoplasmic  secretion;  and, 
secondly,  because  it  is  wanting  in  many  Protozoans 
and  even  in  many  animalcula  quite  high  in  point  of 
organization  that,  despite  their  nudity,  exhibit  marks 
of  psychic  life  just  as  complex  as  those  observed  in 
Infusoria  having  a  cuticle.  The  part  acted  by  the  nu- 
cleus does  not  so  clearly  manifest  itself  to  direct  ob- 
servation; it  executes  no  movements  in  the  ordinary 
conditions  of  life;  it  remains  motionless  in  the  centre 
of  the  animal's  body,  surrounded  on  all  sides  by  the 
protoplasm;  unlike  the  latter,  it  is  not  in  direct  con- 
tact with  the  outside  world. 

The  first  phenomena  that  have  enabled  us  to  con- 
jecture as  to  the  significance  of  the  nucleus,  have  to  do 
with  the  division  of  cellules;  when  a  cellule  divides, 
the  nucleus  comes  into  action,  it  exhibits  certain 


OF  MICR  O-  OR  GANISMS.  93 

movements,  and  passes  through  complicated  stages 
which  have  been  given  the  name  of  caryokinesis.* 

But  these  complex  phenomena  simply  show  the 
function  of  the  nucleus  as  an  histological  element; 
they  do  not  afford  any  disclosures  as  to  the  physiolog- 
ical role  of  the  nucleus  in  the  cellule. 

Other  observations  have  enabled  naturalists  to  sur- 
mise what  phenomena  are  subject  to  the  action  of  the 
nucleus.  In  1881,  Balbiani  called  attention  to  indi- 
viduals, belonging  to  the  species  Param&cium  aurelia, 
that  were  destitute  of  a  nucleus  and  which  neverthe- 
less possessed  the  power  of  locomotion  the  same  as 
ordinary  individuals;  whence,  he  concluded  that  the 
nuclei  exerted  no  influence  upon  the  phenomena  of 
individual  life.  Shortly  afterwards,  Gruber  observed 
small  specimens  of  the  Actinophrys  sol  which  absorbed 
nutriment,  changed  their  position  in  the  liquid,  and 
even  fused  with  each  other  (zygosis),  but  which  were 
nevertheless  destitute  of  a  nucleus.  f 

The  idea  then  occurred  to  Gruber,  and  to  Nuss- 
baum  likewise,  to  divide  the  Micro-organisms  by  ar- 
tificial means  into  several  fragments,  of  which  some 
would  contain  a  nucleus  and  others  not,  and  then  to 
watch  what  would  come  of  it.  Gruber,  to  whose  ex- 
periments the  most  importance  attaches,  chose  as  his 
subject  of  trial  the  Stentor  cceruleus,  a  ciliated  Infu- 
sory  of  great  size,  which  exhibits  a  nucleus  resembling 
a  chaplet  of  beads  (moniliform).  He  afterwards  con- 
tinued his  experiments  upon  other  species,  and  his 
conclusion  was,  that  the  power  to  regenerate  lost  parts 
belonged  to  all  Protozoans,  but  that  this  phenomenon 
only  took  place  when  the  isolated  fragment  contained 


*  Kapvov,  the  nut,  and  nivrjci^,  motion,  disturbance. 

t  Contributions  to  the  Biologisches  Centralblatt,  1885.  p.  73. 


94  THE  PSYCHIC  LIFE 

some  portion  of  the  nucleus;  in  which  case  the  animal 
reproduces  all  the  organs  it  has  lost  in  consequence 
of  its  dissection.  Furthermore,  the  process  of  the  for- 
mation is  exactly  the  same  as  in  the  spontaneous  di- 
vision of  these  same  Infusoria.  The  excitation  caused 
by  their  removal  is  accordingly  of  the  same  character 
as  the  unknown  excitation  that  provokes  the  natural 
division  of  the  body. 

From  these  experiments,  the  part  acted  by  the  nu- 
cleus is  indicated  by  complete  evidence.  Gruber  shows 
that  in  a  single  instance  only  can  a  fragment  without 
a  nucleus  form  itself  anew;  and  that  is,  when  the  frag- 
ment contains  an  organ  in  course  of  formation,  as  hap- 
pens, for  example,  during  the  spontaneous  division  of 
the  animal.  This  amounts  to  saying,  that  the  presence 
of  a  nucleus  is  necessary  to  give  the  impulse  to  the 
formation  of  the  organ,  but  that  it  is  not  necessary  to 
the  completion  of  the  organ  when  the  impulse  has 
once  been  given. 

Lastly,  if  the  fragment  is  totally  destitute  of  a  nu- 
cleus, it  does  not  re-form  itself  so  as  to  constitute  a 
complete  animal  again;  if  the  fragment  possesses  nei- 
ther mouth  nor  peristome,  it  does  not  reproduce  a 
new  mouth  and  a  new  peristome;  yet  the  fragments 
continue  to  live  and  to  move.  The  absence  of  a  nu- 
cleus does  not  suspend  the  functions  of  motion,  sensi- 
bility, nutrition,  or  growth.  This  conclusion  is,  in 
our  estimation,  too  sweeping,  as  we  shall  see  fur- 
ther on.* 

M.  Balbiani  has  recently  repeated  these  experi- 
ments of  artificial  division,  and,  while  confirming  in 


•  We  have  taken  as  oar  guide,  with  the  permission  of  M.  Balbiani,  the  lec- 
tures delivered  by  that  eminent  authority  at  the  College  de  France,  in 
May,  1887. 


OF  MICR  O-  OR  GANISMS. 


95 


general  the  results  of  Gruber  as  to  the  function  of  the 
nucleus  in  the  vital  phenomena  of  ciliated  Infusoria, 
he  has  endeavored  to  fix  with  more  exactness  a  cer- 
tain number  of  important  points.  His  first  experi- 
ments, like  those  of  Gruber,  were  conducted  upon  the 
Stentor  cceruleus,  a  species  of  which  the  size  renders  it 
better  adapted  to  this  sort  of  experimenting.  In  an 
observation  which  we  shall  take  as  a  type,  and  which 
is  represented  by  the  figure  sent  to  us  by  M.  Balbiani, 
the  body  of  the  Stentor  is  cut  by  two  transverse  sec- 
tions; three  divisions  are  obtained,  each  of  which  con- 
tains a  fragment  of  the  nucleus.  We  will  remember 
that  the  nucleus  of  the  Stentor  is  like  a  long  string  of 
beads;  it  is  not  at  all  rare  to  see  a  fragment  of  a  Sten- 
tor contain  one  or  more  beads. 


Fig.  12. — Artificial  division  of  the  Stentor  cterttleus. 
(After  Balbiani.) 

Let  us  follow  the  phenomena  presented  in  the 
middle  segment.  This  segment  contains  only  a  single 
grain  of  the  nuclear  chaplet;  directly  after  severance, 
it  assumed  a  globular  shape;  the  day  following,  it  had 
lengthened,  had  grown  a  tail  at  the  posterior  extrem- 
ity, and  upon  the  anterior  part  there  had  appeared, 
distinctly  outlined,  a  crown  of  cilia  longer  than  those 
upon  the  body;  in  other  words,  a  peristome  had 


96  THE  PSYCHIC  LIFE 

formed;  the  day  after,  the  fragment  had  increased 
considerably  in  bulk,  and  in  two  days  more  the  ani- 
mal had  formed  a  mouth.  During  this  time,  the  nuclear 
grain  had  multiplied:  five,  in  fact,  were  counted.  The 
animal  had  the  normal  form;  its  size,  however,  was  a 
little  smaller  than  that  of  the  ordinary  Stentors. 
Thus,  through  the  action  of  a  small  quantity  of  nu- 
clear substance,  the  fragment  has  been  completely  re- 
constructed. 

It  frequently  happens  that  the  artificial  severing  of 
the  animal  causes  various  deformations  in  the  frag- 
ments. The  deformation  disappears  with  the  greatest 
rapidity  in  fragments  containing  nuclear  substance. 
The  wound  heals  instantly;  directly  after  severance, 
the  two  edges  of  the  wound  are  seen  to  adjust  them- 
selves to  each  other. 

In  all  these  particulars,  the  experiments  confirm 
the  results  obtained  by  Gruber. 

M.  Balbiani  desired  to  ascertain  what  would  hap- 
pen if  the  division  were  made  during  the  state  of  con- 
jugation. 

Conjugation,  as  we  know,  aims  at  replacing  an  old, 
spent  element,  that  has  lost  its  physiological  proper- 
ties, by  an  element  of  new  formation  proceeding  from 
an  attendant  nucleus  (nucleolus)  exchanged  between 
the  individuals  in  conjugation.  The  point  in  question 
was  to  ascertain  whether  the  nucleus  that  was  be- 
ginning to  disappear,  had  lost  its  regenerative  power. 
In  the  Stentors,  during  conjugation,  this  old  nucleus 
breaks,  and  its  nuclear  globules  are  scattered  to  all 
parts  of  the  protoplasm.  When  at  this  stage,  the  body 
of  one  of  the  Stentors  is  divided  in  such  a  manner  that 
the  fragment  contains  some  of  the  scattered  globules 
that  came  from  the  old  nucleus.  It  is  quite  evident 


OF  MICR  O-  OR  G  AN  I  SMS.  97 

that  such  a  fragment  is  obtainable  only  by  mere  acci- 
dent. 

In  an  experiment  which  we  again  cite  as  a  type  of 
many  others,  the  fragment  containing  the  elements  of 
the  old  nucleus  tends  to  reconstruct  itself;  this  frag- 
ment, which  represented  the  posterior  part  of  the 
animal,  presented,  the  day  following,  a  rudimentary 
peristome;  the  reconstruction  did  not  go  beyond  this 
point:  it  was  left  incomplete.  Accordingly,  the  old  nu- 
cleus loses  its  power  of  regeneration. 

As  to  the  phenomena  presented  in  fragments  con- 
taining no  nuclear  substance,  M.  Balbiani  has  made 
decided  advances  in  the  question;  he  has  completed  the 
experiments  of  Gruber,  he  has  also  corrected  them, 
and  he  has  reached  conclusions  essentially  different. 

In  order  to  understand  more  thoroughly  the  phe- 
nomena connected  with  the  absence  of  nuclear  sub- 
stance, the  author  has  directed  his  attention  to  an- 
other species,  the  Cyrtostomum  leucas,  which  has  the 
advantage  that  it  can  be  kept  longer  alive  than  the 
Stentor  can,  on  a  glass  slide  holding  a  drop  of  water. 
The  Cyrtostomum  is  a  large  ciliated  Infusory  of  more 
than  four-tenths  of  a  millimeter  in  length.  Its  proto- 
plasm is  differentiated  into  two  layers,  one  of  which, 
the  cortical,  encloses  very  heavy  trichocysts;  the  other, 
the  endoplasm,  holds  alimentary  substances.  The  an- 
imal exhibits  upon  one  of  its  faces  a  mouth,  shaped 
like  a  long  narrow  buttonhole,  and  upon  the  other 
face  a  contractile  vesicle,  from  which  crooked  and  an- 
astomosed passages  radiate.  It  is  easy,  by  making  a 
transversal  division,  to  obtain  fragments  without  nu- 
clear matter;  the  nucleus  of  the  Cyrtostomum  being 
formed  of  a  single,  round  mass.  But  it  is  not  easy,  on 
the  other  hand,  to  obtain  fragments  likely  to  live, 


98  THE  PSYCHIC  LIFE 

since  this  animalcule  has  a  dense  ectoplasm,  and, 
when  severed,  this  layer,  which  is  not  very  retractile, 
does  not  grow  together  again  and  close  the  wound; 
the  sides  remain  separated,  the  water  comes  in  con- 
tact with  the  endoplasm,  which  swells,  bulges  out,  and 
runs  from  the  wound;  the  animal  may  thus  void  itself 
completely,  dying  of  diffluence.  It  occasionally  hap- 
pens that  the  animal  voids  itself  only  in  part,  and  that 
the  nucleus  escapes  with  a  small  piece  of  the  proto- 
plasm. Then,  if  the  wound  draws  together,  we  get  a 
fragment  that  has  thrown  out  the  nucleus  by  its  own 
action. 

We  shall  not  speak  of  the  actions  of  the  fragment 
containing  nuclear  substance;  they  are  the  same  as 
observed  in  the  case  of  Stentors:  the  fragment 
rapidly  reconstructs  itself  and  re-forms  a  complete 
animal. 

Let  us  mark  more  closely  the  fragment  without  nu- 
cleus. Such  fragments  continue  to  live  for  some 
time;  they  have  been  kept  alive  as  long  as  eight  days; 
but  they  do  not  reconstruct  themselves;  they  do  not 
even  assume  a  regular  form;  the  part  of  the  body  fac- 
ing the  section  retains  its  obliquity  of  truncation.  At 
the  start,  for  the  first  few  days,  the  movements  con- 
tinue; a  curious  circumstance  connected  therewith  is, 
that  the  fragments  continue  to  move  in  the  direction 
in  which  they  would  have  moved  if  they  were  placed 
together  to  form  a  complete  individual.  The  vibratile 
cilia  are  in  no  wise  altered;  they  shake  with  the  same 
animation  as  before.  Only  the  movements  of  the  an- 
imal are  a  trifle  irregular;  but  they  exhibit  the  same 
marks  of  volition  as  seen  in  normal  individuals.  The 
vesicle  continues  to  contract. 

The  power  to  seize  food  is  also  retained  when  the 


OF  MICR O-  OR  GANISMS.  99 

fragment  without  nucleus  contains  the  mouth;  the 
mouth  ingests  alimentary  substances.  If  the  Cyrtosto- 
mum  be  given  grains  of  potato  fecula,  which  it  is  very 
partial  to,  the  fragment  without  nucleus,  but  with  a 
mouth,  swallows  these  grains  and  fills  itself  with  them. 
It  is  not  known  whether  it  digests  them. 

This  much  was  observed  in  the  first  stages,  and 
Gruber  was  wrong  in  stopping  at  this  point. 

At  the  expiration  of  a  certain  time,  varying  be- 
tween the  third  and  fourth  day,  alterations  of  structure 
are  noticed  in  the  fragment  that  are  probably  traceable 
to  the  absence  of  the  nucleus.  One  of  the  first  to  take 
place  is  the  disappearance  of  the  marks  of  differentia- 
tion which  we  have  observed  to  distinguish  the  endo- 
plasm  from  the  ectoplasm.  The  dark  granules  that 
fill  the  interior  of  the  body  congregate  in  the  centre 
by  abandoning  the  peripheral  part;  then  these  granules 
scatter  and  come  to  a  position  just  beneath  the  cuticle, 
which  denotes  a  deliquescence  of  the  plasma.  The 
layer  of  trichocysts  undergoes  changes  and  disap- 
pears. All  these  alterations  result  from  an  actual  dis- 
organization of  the  plasma.  The  contractile  vesicle 
shrinks,  its  pulsations  decrease,  the  radiating  passages 
disappear.  The  body  of  the  animal,  which  in  its  nor- 
mal condition  is  elongate,  becomes  rounded;  its  move- 
ments flag  and  consist  of  nothing  but  a  rotation  of 
the  body  about  its  own  axis;  at  last  the  animal  be- 
comes motionless  and  dies  of  diffluence. 

These  changes  are  not  due  to  lack  of  sustenance, 
as  one  might  suppose;  for  fragments  that  have  a 
mouth  and  swallow  food,  pass  through  the  same  alter- 
ations as  those  that  have  no  mouth.* 


*  M.  Balbiani  has  informed  us,  upon  request,  that  the  fragments  of  Cyr- 
tostomum  furnished  with  nucleus  can  be  kept  alive  for  a  much  longer  time 


ioo  THE  PSYCHIC  LIFE 

It  is  superfluous  to  insist  upon  the  importance  of 
these  results,  obtained  by  a  method  that  might  be 
called  experimental  physiology  applied  to  unicellular 
organisms.  Although  the  experiments  have  been 
made  solely  with  ciliated  Infusoria,  the  results  of  the 
same  may  be  extended  to  all  cellules,  for  the  Infusoria 
are  nothing  more  than  autonomous  cellules  living  an 
independent  life. 

The  conclusion  from  the  above  researches  of  M. 
Balbiani,  which,  as  we  have  seen,  go  far  beyond  those 
of  Gruber,  is,  that  the  nucleus  is  not  necessary  merely 
to  the  regeneration  of  the  parts,  as  the  German  pro- 
fessor believed.  The  error  made  by  Gruber  arose 
from  the  fact  that  he  did  not  follow  the  career  of  the 
fragments  deprived  of  a  nucleus  long  enough;  if  he 
had  continued  his  observations,  he  would  have  seen 
that  the  fragment  becomes  gradually  disorganized. 
The  nucleus,  accordingly,  has  not  merely  a  formative 
power;  it  does  not  merely  regulate  alimentation,  re- 
adjustment of  form,  and  the  healing  of  wounds;  it  has 
not  merely  a  regenerative  power,  enabling  the  plasma 
to  reconstruct  complete  the  organs  lost  by  artificial 
severance.  The  nucleus  is,  besides  all  this,  an  essen- 
tial factor  of  the  plasm's  vitality.  If  a  fragment  of 
protoplasm  be  deprived  of  its  nucleus,  the  fragment 
remains  alive  for  some  time,  but  afterwards  under- 
goes disorganization. 

Such  are  the  facts,  extremely  complex,  and  conse- 
quently difficult  to  summarize  by  a  formulated  state- 
ment. 


under  the  same  conditions  (that  is,  in  a  drop  of  water  on  a  glass  slide  kept  in 
the  moist  chamber  of  Malassez):  in  this  way  it  is  possible  to  keep  them  alive 
for  the  space  of  a  month,  by  introducing  into  the  liquid  a  few  Infusoria  to  serve 
them  as  food.  On  the  other  hand,  the  fragments  deprived  of  nucleus  by  sec- 
tion live  for  only  eight  days  at  the  most. 


OF  MICR  O-  OR  GANISMS.  i  o i 

We  certainly  cannot  regard  the  protoplasm  as  in- 
ert matter;  but  what  appears  probable  is,  that  the  pro- 
toplasm receives  from  the  nucleus  the  communication, 
the  delegation  of  physiological  powers.  The  nucleus  is 
in  a  certain  sense  the  focal  seat  of  life  in  all  its  forms. 

If  we  get  rid  of  the  nucleus  by  artificial  section, 
the  fragment  of  enucleated  protoplasm  continues  to 
live  for  some  time,  having  received  from  the  nucleus 
an  impulsion  that  has  not  yet  been  exhausted;  but  af- 
ter a  certain  length  of  time,  the  impulsion  given  by  the 
nucleus  not  being  renewed,  the  protoplasm  runs  its 
course  and  dies. 

From  the  psychical  point  of  view,  which  more  par- 
ticularly occupies  our  attention  here,  how  are  the  re- 
sults of  these  experiments  in  cellular  vivisection  to  be 
explained?  When  a  fragment  of  an  organism,  deprived 
of  nuclear  substance,  is  seen  to  move  about  freely  and 
with  the  same  activity  as  if  it  still  possessed  its  nu- 
cleus, we  are  constrained  to  admit  that  the  phenom- 
ena of  the  life  of  relation,  or  movement  and  sen- 
sibility, have  their  seat  in  the  protoplasm.  But  it  is 
probable  that  such  physiological  capacities  as  the 
powers  of  nutrition,  are  not  inherent  in  protoplasm; 
they  depend  immediately  upon  the  presence  of  the 
nucleus,  for  they  disappear  little  by  little  and  finally 
vanish  a  few  days  after  the  removal  of  the  nucleus.* 

It  may  be  mentioned  in  passing,  that  there  are  cer- 
tain psychical  properties  which  the  nucleus  apparently 
does  not  transmit  to  the  protoplasm,  but  which  it  re- 
tains for  itself;  this  is  the  case  with  the  instinct  of  gen- 


*  The  difficult  question  here,  is  to  ascertain  whether  the  psychical  proper- 
ties of  the  protoplasm  are  destroyed  through  the  direct  effect  of  the  disorgan- 
ization of  the  plasma,  or  whether  they  disappear  a  short  time  before  the 
process  of  disorganization  and  in  consequence  of  the  absence  of  nuclear  sub- 
stance. 


102  THE  PSYCHIC  LIFE 

eration.  We  have  already  seen  that,  during  the  epi- 
demic periods  of  conjugation,  the  Paramecia  which 
have  their  nuclei  overrun  with  parasites  cease  to  con- 
jugate with  animals  of  the  same  species.  The  destruc- 
tion of  their  nucleus  by  the  Bacteria  produces  in  the 
Paramecia  the  effect  of  actual  castration. 

The  removal  of  the  nucleus,  accordingly,  causes 
the  interruption  of  the  following  functions  and  in  the 
following  order  as  to  time: 

1.  The  regenerative  and  reproductive  property  of 
the  plasma; 

2.  The  vitality  of  the  plasma,  and   the  psychical 
functions. 

The  psychologist  will  notice  with  interest  that  the 
psychical  function  of  the  protoplasm  outlives  the  re- 
generative function  for  an  appreciable  length  of  time; 
a  fragment  of  a  cellule  which,  having  been  mutilated 
by  the  act  of  severance,  is  unable  to  correct  its  out- 
ward form,  or  to  secrete  a  fresh  cuticle,  or  to  recon- 
struct its  lost  organs,  is  nevertheless  still  capable  of 
perceiving  sensations  and  of  responding  thereto  by 
movements.  Psychical  life  is  consequently  a  prop- 
erty of  living  matter  which  appears  to  be  less  complex 
than  the  regenerative  property,  inasmuch  as  it  ceases 
later. 

To  summarize,  the  nucleus  plays  the  primordial 
role  in  the  cellule;  if,  to  use  an  old  comparison  of  Ar- 
istotle's, we  compare  the  protoplasm  to  the  clay,  we 
must  compare  the  nucleus  to  the  potter  that  fashions 
it.  The  nucleus  comprehends  all  the  physiological 
properties,  the  totality  of  which  goes  to  constitute 
life. 

It  is  interesting  to  note  what  perfect  accord  pre- 
vails between  these  recently  discovered  facts  and  the 


OF  MICR  O-  OR  CAN  I  SMS.  1 03 

phenomena  relative  to  fecundation.  Fecundation  con- 
sists in  the  fusion  of  two  nuclei,  of  which  one  proceeds 
from  the  male,  and  one  from  the  female.  Thus,  it  is 
through  the  intermediary  office  of  the  nucleus  that  all 
the  faculties,  all  the  properties  possessed  by  the  par- 
ents,— the  form  of  their  bodies  as  well  as  their  psychi- 
cal faculties, — are  transmitted  to  the  embryo;  as  we 
have  just  remarked,  therefore,  all  these  properties 
must  be  comprehended  in  the  nucleus,  in  order  to  pass 
into  the  embryo. 

We  must  note  further,  that  the  embryo  takes  from 
the  mother  something  besides  the  nucleus.  While  it  is 
connected  with  the  father  through  the  head  of  the 
spermatozoid,  which  has  the  morphological  value  of  a 
nucleus,  it  receives  from  the  mother  not  only  the  fe- 
male nucleus  but  also  the  vitelline  plasma  of  the 
ovule;  now,  as  the  embryo  does  not  exhibit  a  greater 
morphological  likeness  to  the  mother  than  to  the  fa- 
ther, we  may  thence  infer  that  the  vitelline  protoplasm 
inherited  from  the  mother  exerts  no  formative  influ- 
ence upon  the  development  of  its  body. 

These  are  not  the  only  facts  the  connection  of 
which  we  desire  to  show  with  the  results  of  experi- 
ments upon  the  function  of  the  nucleus.  It  will  be  well 
to  point  out  here,  how  reproduction  is  effected  among 
organisms  which,  besides  their  nucleus,  possess  other 
differentiated  organs.  The  best  known  and  perhaps 
the  most  general  mode  of  reproduction  is  fissiparity, 
which  consists  in  a  division  of  the  entire  body  into  two 
equal  parts.  If  we  closely  follow  the  course  of  this 
phenomenon  in  any  organism  whatever,  we  shall  find 
that  the  division  begins  by  a  multiplication  of  the 
principal  organs  of  the  body.  The  nucleus  begins  by 
lengthening  out  and  assuming  a  position  perpendicu- 


104  THE  PSYCHIC  LIFE 

lar  to  the  plane  of  division.  The  first  organ  that  mul- 
tiplies is  the  flagellum;  it  does  not  split  into  two  parts, 
as  several  English  authors  have  supposed;  according 
to  the  observations  of  Biitschli  and  of  Klebs,  a  second 
flagellum  is  formed  complete.  The  pigmentary  spot 
also  does  not  divide  into  two  parts;  the  old  eye  re- 
mains by  a  sort  of  preference  with  one  of  the  parts, 
while  the  other  part  acquires  a  new  eye,  formed  com- 
plete; this  is  likewise  the  case  with  the  mouth  and  the 
oesophagus.  There  are  only  two  elements  that  multi- 
ply by  division:  the  chromatophores  and  the  nucleus 
Now,  when  we  note  that  the  chromatophores  contain  a 
body,  the  pyrenoid,  which  exhibits  the  closest  analogy 
of  chemical  composition  with  the  nucleus,  we  may 
properly  say  that  the  nuclear  elements  of  the  cellule 
are  the  only  ones  that  do  not  reproduce  by  neoforma- 
tion  at  the  expense  of  the  protoplasm,  as  is  the  case 
with  the  cilia  and  the  flagella. 

The  reason  for  this  mode  of  multiplication  by  nu- 
clear elements  will  be  comprehended,  if  we  consider 
the  matter  in  the  light  of  experiments  made  upon  the 
formative  properties  of  the  nucleus.  We  have  seen, 
in  fact,  that  the  nucleus  can  regenerate  the  protoplasm, 
but  that  the  protoplasm  cannot  regenerate  the  nucleus. 
We  now  see  that  the  regeneration  of  organs  lost  in 
consequence  of  the  spontaneous  division  of  cellules,  is 
subjected  to  the  same  law  as  the  regeneration  follow- 
ing upon  artificial  division;  the  protoplasm  cannot  re- 
generate a  nuclear  element  any  more  in  the  one  case 
than  in  the  other;  in  order  to  effect  reproduction, 
therefore,  this  element  must  divide. 


OF  MICR O-  OR GANISMS.  1 05 

IX. 

CONCLUSION. 

THE  conclusions  relative  to  psychological  phenom- 
ena arrived  at  in  the  foregoing  treatise,  are  in  contra- 
diction with  the  opinions  generally  received  upon  the 
psychology  of  the  cell.  Scientists  have  held,  that  cell- 
ular psychology  is  represented  wholly  and  solely  by 
the  laws  of  irritability.  In  his  Essai  de  Psychologic 
Generate,  a  work  in  so  many  respects  remarkable,  M. 
Richet  has  assumed  the  advocacy  of  this  view;  the 
correctness  of  which  we  have  no  hesitation  in  disput- 
ing. In  the  work  just  mentioned,  the  distinguished 
professor  has  written  the  following: 

"There  exist  simple  beings  which  appear  to  be 
nothing  more  than  a  homogeneous  assemblage  of  irri- 
table cellules.  Motory  reaction,  consequent  upon 
irritation  from  without,  constitutes  their  life  of  rela- 
tion. Irritability  is  their  life  complete,  but  this,  in 
effect,  is  psychic  life;  so  that  cellular  irritability  can 
be  considered  the  same  as  elementary  psychic  life." 

From  an  attentive  perusal  of  this  passage  it  will 
be  seen  that  M.  Richet  brings  within  the  category  of 
irritability,  not  only  unicellular  organisms,  but  also 
pluricellular  organisms  formed  by  the  union  of  homo- 
geneous cellules. 

M.  Romanes,  in  his  work  upon  Mental  Evolution, 
without  coming  to  a  conclusion  so  definite  as  M. 
Richet,  seems  to  us  to  have  reduced  the  psychic  ac- 
tivity of  proto-organisms  to  within  very  narrow  limits. 
We  are  impressed  with  the  fact  upon  glancing  over 
his  Diagram  of  Mental  Evolution :  he  recognizes 
nothing  but  excitability,  for  example,  in  the  ovule  and 
spermatozoid  of  man.  This  is  manifestly  erroneous. 


io6  THE  PSYCHIC  LIFE 

The  sexual  elements,  and  especially  the  spermatozoid, 
of  all  unicellular  organisms  are  certainly  the  ones  which 
show  the  most  highly  developed  psychical  functions: 
the  act  of  seeking  and  approaching  the  ovule,  which 
is  frequently  situated  at  quite  some  distance  from 
where  the  male  element  is  deposited;  the  length  of 
road  to  be  traveled;  the  obstacles  to  be  overcome; 
all  point  to  faculties  in  the  spermatozoid  that  are  not 
explainable  by  simple  irritability. 

Hitherto,  apparently,  writers  who  have  essayed  to 
present  the  psychology  of  micro-organisms,  have  con- 
tented themselves  with  schematic  notions  instead  of 
basing  their  theories  upon  the  direct  observation  of 
these  interesting  creatures.  By  the  aid  of  exact  data, 
we  have  shown  that  in  both  vegetable  and  animal 
micro-organisms  phenomena  are  encountered  which 
pertain  to  a  highly  complex  psychology,  and  which 
appear  nuite  out  of  proportion  to  the  minute  mass 
that  s-  them  as  a  substratum. 

We  .xall  first  of  all  advert  to  the  term  irritability, 
which,  though  long  in  use,  has  not  in  our  opinion  been 
happily  chosen:  since  it  is  in  the  highest  degree  ambig- 
uous, and  no'  suggestive  of  an  exact  signification. 
We  might  call  to  mind  in  this  connection,  the  reflec- 
tion made  by  Kant  upon  obscure  properties,  which  he 
compares  to  easy-chairs  upon  which  the  mind  unbends 
itself  and  rests.  In  place  of  discussing  words,  let  us 
endeavor  to  discuss  facts. 

What  are  we  to  understand  by  irritabilitv?  We 
may  give  the  expression  a  very  broad  or  a  very  re- 
stricted meaning.  We  may  make  it  express  the  prop- 
erty which  every  organism  possesses,  of  reacting 
upon  excitation.  In  this  general  sense  we  may  say 
that  irritability  includes  within  itself  all  of  psychology, 


OF  MICR  O-  OR  GANISMS.  1 07 

the  most  highly  developed,  as  well  as  the  most  ele- 
mentary; for  upon  ultimate  analysis  every  psychical 
manifestation  consists  in  a  response  to  an  excitation. 
Evidently,  it  is  not  in  this  general  and  somewhat 
common  sense  that  M.  Richet  has  intended  to  employ 
the  word.  For  a  more  exact  definition,  let  us  consult 
his  work,  of  which,  a  whole  chapter,  the  first,  is  de- 
voted to  this  subject;  the  author  enumerates  and  de- 
velops at  length  the  laws  of  irritability: 

1.  Every  action  that  modifies  the  actual  condition 
of  a  cell  is  an  irritant  of  that  cell. 

2.  Every  external  force,  provided  it  has  a  certain 
intensity,  is  capable  of  inducing  cellular  irritability. 

3.  The  movement  in  response  to  irritation  is  pro- 
portional to  the  excitation. 

4.  The  movement  in  response  to  irritation  is,  for 
equal  irritations,  stronger  in  proportion  as  the  equilib- 
rium of  the  cell  is  less  stable;  in  other  words,  stronger 
in  proportion  as  the  cell  is  more  excitabL         ,a 

5.  The  response  to  the  irritation,  is  a  n,,a-tment  in 
the  form  of  a  wave,  which  has  a  very  short  latent  pe- 
riod, a  period  of  ascent,  correspondingly  brief,  and  a 
very  long  period  of  descent.  •,   j 

6.  The  movement  of  the  cell  upon  irritation  is,  for 
equal  irritations,  stronger  in  proportion  as  the  irrita- 
tion has  been  more  sudden. 

7.  The  movement  in  response  to  a  brief  irritation 
lasts  much  longer  than  the  irritation  has  lasted. 

8.  Forces  which,  alone,  appear  impotent,  become 
effective  when   repeated;  for  they  have,  in  spite  of 
their  apparent  inefficacy,  increased  the  excitability  of 
the  organism. 

The  statement  of  these  various  laws,  gives  the  term 
irritability  a  precision  which  it  lacked.    M.  Richet  had 


io8  THE  PSYCHIC  LIFE 

in  view  particularly  the  muscular  fibres,  and  the  laws 
of  irritability  are  only  supposed  to  cover  a  series  of 
physiological  experiments  made  upon  the  reaction  of 
a  striated  muscle.  They  are  not,  then,  hypothetical 
laws,  but  are  much  rather  particular  experiments  gen- 
eralized and  extended  to  undifferentiated  protoplasm. 
It  is  proper  to  remark  here,  that  we  have  not  as  yet 
been  able,  by  means  of  direct  experiments,  to  ascer- 
tain from  life  the  laws  of  irritability  in  undifferentiated 
protoplasm.  The  experiments  made  upon  this  point, — 
for  instance,  the  experiment  causing  the  protoplasm 
of  a  detached  cell  to  contract  by  means  of  an  electric 
current, — have  not  yet  been  brought  to  a  precise  result; 
for  the  structure  of  protoplasm  is  so  delicate  and  so 
complex,  that  even  the  slightest  excitation  suffices  to 
produce  an  alteration,  and  since  it  is  difficult  to  distin- 
guish the  contraction  of  the  protoplasm  from  its  coag- 
ulation. But  we  shall  pass  by  this  subordinate  ques- 
tion. 

The  question  now  remains,  whether  the  compli- 
cated experiments  made  in  muscular  physiology,  which 
M.  Richet  generalizes  and  extends  to  the  physiology 
of  all  cellules,  include  and  comprehend  the  whole  psy- 
chology of  an  independent  organism,  and  whether  we 
may  say  with  M.  Richet,  that  irritability  (thus  under- 
stood) represents  all  of  cellular  psychology. 

Plainly  not.  The  numerous  facts  which  we  have 
cited  in  the  foregoing  essay,  transcend  the  too  narrow 
limits  within  which  it  has  been  attempted  to  confine 
the  psychology  of  the  cell.  We  shall  restrict  our- 
selves to  the  mention  of  one  of  these  phenomena,  to 
show  the  complexity  of  the  psychic  life  of  micro-organ- 
isms: it  is  the  existence  of  a  power  of  selection,  exer- 
cised either  in  the  search  for  food,  or  in  the  manoeu- 


OF  MICRO-ORGANISMS  109 

vres  attending  conjugation.  This  act  of  selection  is  a 
capital  phenomenon;  we  may  take  it  as  the  character- 
istic feature  of  functions  pertaining  to  the  nervous 
system.  As  Romanes  has  indeed  observed,  the  power 
of  choice  may  be  regarded  as  the  criterion  of  psy- 
chical faculties.  Going  farther,  we  might  be  able  to 
say  that  selection  comprehends  the  properties  of  the 
nervous  cellule,  as  irritability  comprehends  the  prop- 
erties of  the  muscular  cellule. 

Scientists  have  endeavored  to  explain  the  mechan- 
ism of  this  choice.  They  have  pretended  to  solve  it 
by  saying  that  it  was  dependent  upon  the  relation  be- 
tween the  chemical  composition  of  the  cellule  making 
the  choice  and  the  chemical  composition  of  the  body 
selected. 

Such  explanations  are  purely  verbal.  Undoubt- 
edly, the  faculty  of  selection,  of  which  protoplasm 
seems  to  be  possessed,  is  founded  in  the  character 
of  its  chemical  composition.  Chemistry  lies  at  the 
basis  of  physiology,  but  chemistry  does  not  explain 
physiology,  and  it  is  quite  evident  that  that  property 
which  protoplasm  possesses  of  making  a  choice  be- 
tween several  excitations,  is  a  physiological  property. 

However  that  may  be,  we  may  resume  all  the  fore- 
going into  the  statement  that  every  micro-organism 
has  a  psychic  life,  the  complexity  of  which  transcends 
the  limits  of  cellular  irritability,  from  the  fact  that 
every  micro-organism  possesses  a  faculty  of  selection; 
it  chooses  its  food,  as  it  likewise  chooses  the  animal 
with  which  it  copulates. 

M.  Richet  has  defended  his  opinion  in  opposition 
to  the  one  I  have  propounded,  in  a  note  published  in 
the  Revue  Philosophique  for  Febuary  1888,  wherein  he 
speaks  as  follows: 


i  io  THE  PSYCHIC  LIFE 

At  the  beginning  of  his  essay  upon  the  Psychic  Life  of  Micro- 
Organisms  (Revue  Philosophique),  M.  Binet  expresses  himself  as 
follows:  "  In  the  lower  beings  that  represent  the  simplest  forms  of 
life,  we  find  manifestations  of  an  intelligence  which  greatly  trans- 
cends the  phenomena  of  cellular  irritability.  Thus  even  on  the 
very  lowest  rounds  of  the  ladder  of  life,  psychic  manifestations  are 
very  much  more  complex  than  is  usually  believed,  and  the  concep- 
tion of  cellular  psychology  which  some  very  recent  authors  have 
formed,  seems  to  me  a  very  crude  analysis  of  the  most  delicate  of 
phenomena." 

As  I  have  upheld  in  my  Essai  dt  Psychologic  Gtntrale,  and  in  some 
measure — however  little — developed  this  admitedly  old  idea,  that 
cellular  irritability  is  the  beginning  of  psychical  activity,  I  request 
the  permission  to  speak  in  defence  of  an  opinion  so  roughly  han- 
dled by  M.  Binet. 

Now,  it  appears  to  me  that  M.  Binet  has  allowed  himself  to 
become  involved  in  illusion  respecting  the  word  cellule.  A  cell,  in 
the  eyes  of  the  embryologist  and  the  morphologist,  has  a  well-de- 
fined meaning.  But  M.  Binet  does  not  seem  to  have  comprehended 
the  fact,  that  for  the  physiologist  and  the  psychologist,  the  essen- 
tial condition  of  cellular  unity  is  homogeneity.  It  is  possible  that 
the  infusoria,  the  strange  story  of  whose  life  M.  Binet  relates  to 
us,  are  single-celled  organisms.  I  am  in  no  wise  qualified  to  decide 
as  to  this;  but  whether  a  single  cell,  or  a  group  of  cells,  it  matters 
little,  in  my  opinion,  provided  the  single  cell  is  differentiated  to 
the  same  degree  that  it  would  be  if  composed  of  several  cells  not 
homogeneous. 

I  appeal  to  M.  Binet  himself  and  to  the  cuts  of  his  essay.  When 
he  shows  us  an  Euglena  with  eyes,  oesophagus,  mouth,  contractile 
vesicle,  contractile  reservoir  (fig.  6);  when  he  carefully  describes 
the  shape  of  the  flagellurn,  the  nettle-like  tentacles,  the  tongue- 
shaped  organs,  the  ocular  spots,  the  trichocysts,  and  theperistorne; 
when  he  assumes  special  nervous  centres  endowed  with  various  at- 
tributes (p.  22):  he  cannot  induce  us  to  admit  that  the  psychology 
of  these  complicated  organisms  is  the  same  as  the  psychology  of 
the  simple  cell.  I  repeat,  it  is  quite  immaterial  to  me  that  people 
affirm  by  the  authority  of  embryology  that  this  or  that  is  a  single 
cell.  If  that  cellule  have  ocular  organs,  a  nervous  system,  a  mouth, 
an  aesophagus,  and  a  heart,  I  shall,  despite  any  and  every  hypoth- 
esis of  the  embryologists,  refuse  to  regard  it  as  being  physiologi- 
cally a  homogeneous  cell,  as  is,  for  example,  a  muscular  fibre. 


OF  MICR O- ORGANISMS.  1 1 1 

The  size  will  not  affect  the  matter  at  all.  The  same  desires, 
says  Montaigne,  stir  mite  and  elephant  alike.  The  psychic  life  of 
the  bee  is  as  complex  as  that  of  the  whale,  and  if  a  microscopic  in- 
fusory  possess  eyes,  mouth,  prickles,  and  heart,  it  evidently  pos- 
sesses them  in  order  that  it  may  make  use  of  them,  and  accordingly 
I  shall  treat  it  as  a  complex  organism  upon  the  same  ground  that  I 
do  a  snail  or  a  grasshopper.  Embryology  will  not  force  me  to  the 
extremity  of  regarding  such  a  creature  as  a  simple  organism  be- 
cause it  is  derived  from  a  single  cell. 

In  my  opinion,  therefore,  it  is  that  unfortunate  word  unicellu- 
lar, that  has  made  M.  Binet  believe  that,  Infusoria  being  unicel- 
lular organisms,  the  elementary  psychology  of  the  cellule  applied 
to  them.  M.  Binet  has  allowed  himself  to  be  deceived  by  a  word — 
a  thing  that  often  happens  in  matters  of  science.  For  my  own 
part,  in  order  to  avoid  any  confusion,  I  would  like  to  say  that  the 
elementary  psychology  of  the  cellule  ought  not  by  rights  to  be  ap- 
plied to  anything  except  to  homogeneous  cellules;  for  the  psychol- 
ogy that  has  to  do  with  complex  cells — real  organisms  with  organs 
and  apparatus  of  their  own — must  certainly  be  as  complex  as  the 
psychology  of  animals  wholly  differentiated. 

The  laws  of  irritability  act  in  all  their  simplicity  and  rigor 
among  simple  beings.  In  fact,  in  every  instance  of  investigation 
into  the  nature  of  simple  organisms,  or  such  as  appear  simple  by 
the  optical  instruments  at  our  disposal  (a  fact  that  does  not  always 
rigorously  prove  their  simplicity),  as  bacteria,  for  example, — we 
find  that  chemical  irritability  is  the  apparently  sole  law  of  move- 
ment. What  else,  indeed,  are  the  movements  of  those  bacteria  so 
thoroughly  studied  by  M.  Engelmann,  if  not  an  affinity  for  oxygen, 
in  other  words  the  simplest  and  most  universal  chemical  phenom- 
enon in  all  nature? 

And  so  the  critique  of  M.  Binet  will  not  stand.  On  the  con- 
trary, it  seems  to  be  well  established  that  complex  organisms, 
whether  single-celled  or  many-celled,  have  a  psychology  corre- 
sponding in  complexity  to  the  degree  of  differentiation  their  organs 
have  attained,  while  simple  beings — and  they  are  simple  only  if 
homogeneous — have  a  simple  psychology  which  is  probably  con- 
tained in  the  laws  of  Irritability  only.  CH.  RICHET. 

My  reply  to  the  letter  of  M.  Richet,  published  in 
the  same  number  of  the  Revue  Philosophique,  may  be 
offered  as  a  general  conclusion  to  my  work.  With  the 


na  THE  PSYCHIC  LIFE 

omission  of  all  polemical  features,  it  is  in  substance 
as  follows: 

In  giving  the  psychology  of  these  microscopic  creatures  the 
name  of  cellular  psychology,  I  have  not  invented  a  new  term,  nor 
given  a  new  sense  to  an  old  one.  Quite  some  time  before  me,  M. 
Haeckel  had  made  a  study  of  cellular  psychology  and  his  investiga- 
tions, like  my  own,  were  based  entirely  upon  the  observation  of 
animal  and  vegetable  micro-organisms.  Furthermore,  micro-or- 
ganisms being  represented  by  a  single  cellule  (and  this  doctrine  is 
now  universally  accepted),  the  study  of  their  psychical  manifesta- 
tions can,  in  my  opinion,  with  perfect  propriety  be  styled  cellular 
psychology. 

M.  Richet  takes  exception  to  the  use  of  the  latter  expression; 
but  he  does  so  while  substituting  for  the  old  definition  of  the  word 
cell,  one  quite  his  own.  To  him,  a  micro-organism  like  the  Eu- 
glena,  which  has  an  eye,  a  mouth,  an  aesophagus,  and  a  contractile 
vesicle,  would  not  be  a  cellule.  To  admit  the  latter  view,  means, 
in  his  own  words,  to  become  involved  in  illusion  respecting  the 
word  cellule.  In  our  judgment,  the  question  here  is  by  no  means 
one  of  optical  illusion,  but  one  of  verbal  definition.  What,  ac- 
cordingly, is  a  cellule?  "  For  the  physiologist  and  psychologist," 
says  M.  Richet,  "  the  cellule  has  not  a  distinct  entity,  or,  at  least, 
that  entity,  that  unity,  lacks  an  essential  condition,  namely,  homo- 
geneity." 

To  M.  Richet,  the  cellule  is  a  homogeneous  body;  a  body  that 
comprises  differentiated  parts  is  not  a  cellule. 

It  is  unnecessary  to  remark  upon  how  far  the  latter  concep- 
tion of  a  cellule  diverges  from  the  usual  and  commonly  accepted 
definition  of  the  word.  Hitherto,  scientists  have  understood  by 
the  term  cellule,  a  body  made  up  of  the  union  of  two  essential 
parts,  a  quantity  of  protoplasm  and  a  nucleus.  The  scientific  world 
argues  as  to  whether  elementary  forms  exist  which  do  not  contain 
a  nucleus  and  which  should  be  termed  cytodes,  as  proposed  by  M. 
Haeckel.  The  careful  observation  of  micro-organisms  by  means  of 
perfected  technical  processes  has  enabled  us  to  discover  hundreds 
of  nuclei  in  the  very  cellules  which  M.  Haeckel  classed  among  the 
cytodes.  Such  is  notably  the  case  with  many  algae  and  lower-class 
fungi.  The  Moners — a  group  of  micro-organisms  believed  to  have 
no  nucleus — grow  numerically  less  and  less,  in  proportion  as  they 
are  more  carefully  studied.  It  is  true,  we  are  now  no  more  able 


OF  MICR O-ORGA NISMS.  1 1 3 

than  formerly,  to  show  the  presence  of  a  nucleus  in  bacteria;  but 
that  does  not  prove  that  the  bacteria  have  none.  Our  knowledge 
of  the  morphology  of  microscopic  organisms  is  wholly  relative, 
and  depends  upon  the  degree  of  perfection  attained  by  technical 
science.  When  we  bear  in  mind  that  the  presence  of  a  nucleus  re- 
mained for  a  long  time  unobserved  in  organisms  several  hundred 
times  larger  than  the  bacteria,  we  ought  not  to  be  surprised  at  hav- 
ing been  unable  to  discover  one  in  these  smaller  creatures. 

We  may  even  go  further,  and  question  the  material  existence  of 
a  body  formed  solely  of  protoplasm,  basing  our  opinion  upon  the  ex- 
periments of  Gruber,  Nussbaum,  and  Balbiani,  as  reported  in  my 
article,  and  upon  the  more  recent  observations  of  Klebs  which  are 
in  perfect  agreement  with  the  results  of  the  investigators  just  cited. 
All  have  shown  that  the  nucleus  is  an  element  essential  to  the  life 
of  the  cellule,  and  that,  when  a  fragment  of  a  cellular  body  strip- 
ped of  a  nucleus  is  procured  by  artificial  section,  this  fragment  does 
not  reproduce  the  organs  it  lost  by  being  severed;  it  does  not  heal 
its  wound,  it  does  not  refashion  its  form,  and,  what  is  more,  at  the 
end  of  a  certain  time  its  protoplasm,  being  withdrawn  from  the  in- 
fluence of  the  nucleus,  suffers  complete  disorganization.  These 
experiments  were  made  not  only  upon  animal  micro-organisms,  but 
upon  vegetable  cells  also.  They  prove  the  primordial  importance 
of  the  nucleus  in  the  cellule  and  thereby  render  doubtful  the  exis- 
tence of  cellules  deprived  of  a  nucleus. 

Since  every  cellule  contains,  in  all  likelihood,  two  distinct  dif- 
ferentiated elements,  the  protoplasm  and  the  nucleus,  which  have 
neither  the  same  physical  structure,  nor  the  same  chemical  nature, 
nor  the  same  physiological  functions,  we  may  understand  that  it 
would  be  exceedingly  difficult  to  name  a  single  instance  of  a 
simple  homogeneous  cellule.  It  is  the  proper  place  to  add  that 
neither  protoplasm  nor  nucleus,  each  regarded  by  itself,  are  homo- 
geneous substances.  It  is  unnecessary  to  enumerate  all  the  investi- 
gations that  have  been  made  upon  this  point.  Let  us  call  to  mind 
merely  the  fact  that  from  the  morphological  point  of  view  proto- 
plasm appears  to  be  composed  of  two  substances,  a  homogeneous 
semi-liquid  substance  and  a  firmer  substance  exhibiting,  as  auth- 
orities upon  the  subject  say,  sometimes  the  form  of  detached  fila- 
ments and  at  others  a  structure  of  a  reticulate  character. 

At  the  present  day,  accordingly,  it  is  impossible  to  allow  that 
homogeneous  cellules  exist,  without  falling  back  to  Dujardin's 


H4  THE  PSYCHIC  LIFE 

theory  of  the  sarcode.      There  are  really  no  simple  organisms, 
and  such  as  appear  so  are  merely  imperfectly  known. 

However,  it  will  not  do  perhaps  to  take  literally  the  terms  em- 
ployed by  M.  Richet.  When  he  speaks  of  homogeneous  cellules  it 
is  possible  that  he  wishes  to  speak  merely  of  cellules  in  which,  aside 
from  the  nucleus,  no  other  differentiated  organ  is  to  be  found. 

Now,  it  is  quite  important  to  note  that,  even  of  organisms 
made  up  simply  of  protoplasm  and  nucleus,  the  psychology  is  ex- 
tremely complicated,  and  is  not  contained  exclusively  in  the  laws 
of  irritability. 

The  Vampyrella  Spirogyra,  classed  by  Zopf  among  the  animal- 
fungi,  and  the  place  of  which  is  still  so  little  known,  is  a  being  the 
body  of  which  is  composed  of  protoplasm  and  nucleus  simply. 
So  far  no  other  differentiated  organ  has  been  found  in  this  creature, 
except  from  one  to  four  contractile  vesicles.  Employing  the  ter- 
minology of  M.  Richet,  perhaps  we  ought  to  call  this  being  a  sim- 
ple cellule;  yet  this  simple  cellule  has  quite  a  complicated  psy- 
chology: it  exercises  choice  in  the  selection  of  its  food,  attacking 
Spirogyra  only. 

The  same  is  the  case  with  the  Monas  amyli,  which,  having 
neither  eye  nor  mouth,  represents  to  M.  Richet  a  simple  cellule; 
still,  the  Monas  amyli  exercises  choice  in  selecting  its  food,  as  it 
feeds  exclusively  on  grains  of  starch. 

The  structural  elements  of  the  tissues  do  not  differ  from  the 
micro-organisms  whose  psychological  history  I  have  endeavored  to 
unfold,  so  much  as  might  be  imagined:  they  show  the  same  powers 
of  selection,  and  on  this  point  I  shall  only  instance  the  epithelial  cel- 
lules of  the  intestines  or  the  phagocyte  cellules,  the  attributes  of 
which  I  have  described  in  my  essay,  and  which  are  able  to  dis- 
criminate, for  instance,  between  bits  of  fat  and  particles  of  coal, 
absorbing  the  former  and  leaving  the  latter. 

I  repeat  it,  therefore,  no  living  cellule,  strictly  so  defined,  is  a 
simple  cellule,  and  I  do  not  think  that  M.  Richet  has  advanced  a  fit- 
ting illustration  in  mentioning  the  muscular  cell,  for  the  latter  is 
one  of  the  most  highly  differentiated  that  there  are. 

I  cannot  imagine,  accordingly,  to  what  elements,  to  what  be- 
ings clearly  defined,  we  could  apply  the  simple-cellular  psychology 
reduced  to  mere  irritability,  that  M.  Richet  asks  me  to  distinguish 
from  the  complex-cellular  psychology,  which  would  be  exclusively 
reserved  for  the  animal  and  vegetable  micro-organisms  that  I  have 
described. 


OF  MICR  O-  OR  G  AN  I  SMS.  1 1 5 

It  appears  to  me  that  this  simple-cellular  psychology  lacks  a 
foundation;  it  is  a  conception  of  the  mind,  rather  than  a  study 
based  upon  observed  facts. 

In  M.  Richet's  book  I  find  no  indication  as  to  what  sort  of  be- 
ings he  means  to  distinguish  thereby.  He  contents  himself  (pp.  20 
and  27)  with  speaking  of  simple  beings  without  otherwise  defining 
them.  Towards  the  close  of  his  remarks  upon  my  work,  M.  Richet 
cites  an  instance  of  simple  beings,  viz.,  the  bacteria;  in  his  judg- 
ment, chemical  irritability  appears  to  be  the  sole  law  conditioning 
their  movements.  What  are  the  movements  of  the  bacteria,  he 
asks,  if  not  an  affinity  for  oxygen;  in  other  words,  the  simplest  and 
most  universal  chemical  phenomenon  that  exists  in  all  nature? 

In  our  judgment  the  latter  phrase  is  to  be  taken  metaphorically. 
We  believe  that  as  yet  no  one  has  demonstrated  that  the  move- 
ments of  a  living  being,  in  moving  towards  a  distant  object,  how- 
ever simple  they  may  be,  can  be  explained  merely  by  a  chemical 
affinity  acting  between  that  being  and  that  object.  It  is  certainly 
not  chemical  affinity  that  is  acting,  but  much  rather  a  physiological 
need. 

Psychic  life,  like  its  substratum,  living  matter,  is,  when  closely 
studied,  an  exceedingly  complex  subject.  This  fact  is,  with  me, 
a  profound  conviction  ;  it  rests,  not  upon  abstract  ideas  and 
methods,  but  upon  the  observations  that  I  have  given,  observa- 
tions that  are  not  founded  upon  my  own  personal  authority  alone, 
but  which  are  drawn  from  the  highest  authorities,  and  most  of 
which  I  have  been  able  to  verify  with  my  own  eyes. 

ALFRED  BINET. 


n6 


THE  PSYCHIC  LIFE 


APPENDIX. 

The  subjoined  cuts,  explanatory  of  the  conjugation 
of  Micro-organisms,  refer  respectively  to  the  descrip- 
tions on  pages  67,  67  and  68,  68,  69  and  70,  71  and  72. 


Fig.  7  a.— Positions  preliminary  to 
conjugation  among  the  Paramtecium 

aurelta.     (Balbiani.) 


Fig.  7  *.— Several  pairs  of  Stentar 
ccrruleut  fixed  upon  a  conferva  fila- 
ment, enlarged  fifteen  diameters 
(after  Balbiani). 


Fig  7  c.  Position  preliminary  to 
the  copulation  of  the  Stytonyckia 
ntytilus.  The  two  animals  are  super- 
imposed upon  each  other  by  their 
ventral  faces  (Balbiani). 


OF  MICRO-ORGANISMS. 


117 


mcf 


Fig.  7  d.~ Gemmiform  conjugation  of  the  Vorticellinss  (Carchesz'um  poly- 
finum).  A,  first  stage:  the  microgonidium  mi  has  fastened  itself  by  a  filament 
upon  the  peduncle  of  the  macrogonidium.  B,  a  more  advanced  stage:  the  mi- 
crogonidium has  fastened  itself  directly  upon  the  body  of  the  macrogonidium, 
and  its  substance  begins  to  penetrate  into  the  latter.  In  both  individuals  the 
nucleus  has  separated  into  small  rounded  fragments,  and  in  the  microgonidium 
are  seen  the  two  striated  segments  resulting  from  the  division  of  its  nucleolus. 
C,  last  stage  of  the  conjugation.  The  microgonidium,  completely  void  of  its 
contents,  remains  attached  to  the  body  of  the  macrogonidium  under  the  form 
of  a  minute  hollow  tube,  which  in  the  end  drops  away, — ma,  macrogonidium; 
mi,  microgonidium;  «,  nucleus;  nu,  nucleolus;  v.  c.,  contractile  vesicle.  (Figures 
from  M.  Balbiani.) 


n8 


THE  PSYCHIC  LIFE 


EXPLANATION    OF    FIG.    7  E. 

In  the  Chilodon  cu- 
cullulus  the  following  is 
the  series  of  phenomena 
W!f,,w;3o-.    presented  (the  row  of  fig- 
**•§  «i '<H~OV  I    ures  given  opposite,  have 
been    procured    through 
the  kindness  of  M.  Bal- 
biani,  and  will  serve  to  il- 
lustrate our  description): 
The  figure  A  shows  the 
beginning  of  conjugation; 
each  animal  is  shown  with 
its  mouth  (f>),  its  multiple 
contractile  vesicles  (v.  c. ), 
its  nucleus  (n),  and  its  nu- 
cleolus  (nu)\  the  nucleo- 
l  c'g  §  jj    lus  will  become  the  main 
£. «  2  «  &  2  •-    seat  of  the  modifications 

5F  «3  ,£    oc  O   C  J3 

e  2  *  B  *  o--    effected    in   fecundation. 

™   >   l       M  **  *«  J3 

"Sbo  2  H  §  %  *  1°  ^e  figure  .5  the  prin- 
cipal change  pertains  to 
the  nucleolus;  in  each  of 
the  two  animals,  the  nu- 
cleolus has  moved  away 

§.£  S^C-nJJ    from  the  nucleus  and  has 

S  •*       9  n  i:  o 

begun  to  break  apart  into 
two  segments;  the  nucleus 
commences  to  show  signs 
of  regression.  Between 
the  figure  y?and  the  figure 
C  phenomena  take  place 
of  the  highest  importance, 
but  which  are  still  the 
subject  of  dispute.  The 
following  appears  from 
present  investigations  to 
be  the  most  probable:  the 
two  animals  in  conjuga- 
tion exchange  with  each 


OF  MICR  O-  OR GANISMS.  1 1 9 

other  one  of  the  capsules  produced  by  the  division  of  the  nucleolus, 
so  that  when  we  come  to  the  phase  of  the  process  represented  in 
figure  C,  we  find  an  animal  which  contains,  besides  its  nucleus,  two 
nucleolar  segments  in  immediate  proximity  (««'  nu');  it  was  the 
same  in  figure  B;  each  animal  already  possessed  two  nucleolar  seg- 
ments, but  these  segments  were  obtained  from  the  division  of  the 
nucleolus  properly  belonging  to  the  animal  itself,  while  in  figure  C, 
in  consequence  of  an  exchange  effected,  one  of  the  nucleolar  seg- 
ments belongs  originally  to  each  animal  and  the  other  comes  from 
its  mate. 

M.  Balbiani,  who  made  the  first  observations  upon  these  phe- 
nomena of  a  nature  so  delicate  and  complex,  originally  supposed 
that  the  two  adjacent  nucleolar  segments,  which  have  been  rep- 
resented in  the  figure  C,  were  produced  by  the  longitudinal  di- 
vision of  the  nucleolus  exchanged  between  the  two  animals  in  con- 
jugation. 

M.  Maupas  has  recently  proposed  a  different  explanation, 
which  seems  to  be  further  corroborated  by  the  very  figure  given 
twenty  years  previously  by  M.  Balbiani.  According  to  M. 
Maupas  the  segment  exchanged  proceeds  to  fuse  with  the  segment 
not  exchanged,  in  order  to  form  a  compound  segment;  the  two  con- 
tiguous segments,  seen  in  figure  C,  would  not,  therefore,  be  the  re- 
sult of  the  division  of  one  segment  solely,  but  the  first  stage  of  the 
conjugation  of  two  elements  having  different  origins.  A  fact  which 
apparently  argues  in  favor  of  this  opinion,  is  the  aspect  presented 
by  the  two  segments;  if  they  proceed  from  a  division,  we  would 
find  there  certain  phenomena  of  caryokinesis,  which  were  further- 
more completely  unknown  at  the  time  when  M.  Balbiani  made  his 
first  observations. 

However  this  may  be,  it  is  seen  by  figure  C  that  the  regression 
of  the  old  nucleus  (»)  is  sharply  marked. 

In  the  figure  D,  the  two  nucleolar  segments  have  fused  to- 
gether and  have  formed  a  compound  segment,  which  segmentates  in 
its  own  turn;  the  two  new  products  of  that  segmentation  grow  to 
unequal  sizes;  the  largest  capsule  attains  a  size  of  forty  thou- 
sandths of  a  mm. ;  it  is  this  that  forms  the  new  nucleus  of  the 
Chilodon.  The  second  capsule  shrinks  and  becomes  compressed, 
it  takes  its  place  beside  the  first  one  and  becomes  the  new  nucleolus. 

The  figure  E  represents  the  last  stage  of  the  phenomenon;  the 
animal  is  in  possession  of  its  new  nucleus  and  its  new  nucleolus; 


120  THE  PSYCHIC  LIFE 

the  old  nucleus  is  reduced  to  a  small  pale  and  rumpled  mass  and 
will  shortly  disappear. 

To  recapitulate,  then,  if  the  opinion  of  M.  Maupas  (who  did 
not  study  this  species,  but  like  ones)  be  accepted,  the  nucleolus  di- 
vides into  two  capsules:  the  one,  playing  the  part  of  a  male  ele- 
ment, is  exchanged  between  the  two  animals  in  conjugation,  and 
proceeds  to  fuse  with  one  of  the  capsules  derived  from  the  division 
of  the  nucleolus  of  the  other  animal;  the  other  capsule,  which  acts 
the  part  of  a  female  element  fuses  in  the  same  way  with  the  male 
element  coming  from  the  other  animal.  The  result  of  that  fusion 
is  a  compound  capsule  which,  undergoing  a  process  of  division,  pro- 
duces the  new  nucleus  and  the  new  nucleolus  of  the  animal  fecun- 
dated. 


ADDENDA. 

NOTES,  References,  Authorities,  etc.,  omitted  in  the  text: 

Page  i,  line  16.  The  doctrine  of  unicellularity  in  regard  to  the 
Infusoria  has  been  upheld  by  Sibold  and  Kolliker;  the  ma- 
jority of  naturalists  have  conceded  it. 

Page  9,  line  21,  et  seq.,  vide  Pfiiiger's  Arch.,  Vol.  XXIII,  1880. 

Page  10,  line  4,  vide  Rouget,  Revue  Scientifique.  March  15,  1884. 

Page  10,  line  13,  videAnna/es  des  Sciences  Naturelles,  1835,  Vol.  IV, 
pp.  348  and  361. 

Page  12,  line  29,  et  seq.,  vide  Arbeiten  aus  dem  zoblog.  Institut  in 
Wiirzburg,  herausgegeben  von  Prof.  C.  Semper,  Vol.  I.  p. 
9,  1872. 

Page  15,  lines  12  and  13,  vide  Morphologisches  jfahrbuch,  Vol.  X. 
1885,  p.  534. 

Page  16,  line  25,  vide  Pftiiger's  Arch.,  1876. 

Page  19,  line  28,  vide  Balbiani,  Lecons  sur  les  Sporozoaires . 

Page  20,  line  6.  By  protoplasm  in  this  connection  is  understood 
the  entire  cellular  body;  the  distinction  of  function  between 
the  protoplasm  properly  so  called,  and  the  nucleus,  is  estab- 
lished later  on  in  the  essay. 

Page  26,  lines  9  and  10,  vide  Comptes  rendus  de  FAcad.  des  Sciences, 
Nov.  2,  1886,  No.  18. 

Page  29,  line  26,  vide  Bot.  Zeitung,  1881,  1883,  1884,  1886. 

Page  46,  last  line,  vide  E.  Maupas,  Etude  des  Infusoires  ciltts, 
Arch,  de  zool.  exptr.,  1883,  No.  4. 

Page  58,  lines  30  and  31,  vide  Henneguy,  Sur  la  reproduction  du 
Volvox  dioique.  Acad.  des  Sciences,  July  24,  1876. 


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